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1 From whence come wars and fightings among you? come they not hence, even of your lusts that war in your members? 2 Ye lust, and have not: ye kill, and desire to have, and cannot obtain: ye fight and war, yet ye have not, because ye ask not. 3 Ye ask, and receive not, because ye ask amiss, that ye may consume it upon your lusts. 4 Ye adulterers and adulteresses, know ye not that the friendship of the world is enmity with God? whosoever therefore will be a friend of the world is the enemy of God. 5 Do ye think that the scripture saith in vain, The spirit that dwelleth in us lusteth to envy? 6 But he giveth more grace. Wherefore he saith, God resisteth the proud, but giveth grace unto the humble. 7 Submit yourselves therefore to God. Resist the devil, and he will flee from you. 8 Draw nigh to God, and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye double minded. 9 Be afflicted, and mourn, and weep: let your laughter be turned to mourning, and your joy to heaviness. 10 Humble yourselves in the sight of the Lord, and he shall lift you up. 11 Speak not evil one of another, brethren. He that speaketh evil of his brother, and judgeth his brother, speaketh evil of the law, and judgeth the law: but if thou judge the law, thou art not a doer of the law, but a judge. 12 There is one lawgiver, who is able to save and to destroy: who art thou that judgest another? 13 Go to now, ye that say, To day or to morrow we will go into such a city, and continue there a year, and buy and sell, and get gain: 14 Whereas ye know not what shall be on the morrow. For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away. 15 For that ye ought to say, If the Lord will, we shall live, and do this, or that. 16 But now ye rejoice in your boastings: all such rejoicing is evil. 17 Therefore to him that knoweth to do good, and doeth it not, to him it is sin.
[AD 99] Clement of Rome on James 4:1
Such examples, therefore, brethren, it is right that we should follow; since it is written, "Cleave to the holy, for those that cleave to them shall [themselves] be made holy." And again, in another place, [the Scripture] says, "With a harmless man you shall prove yourself harmless, and with an elect man you shall be elect, and with a perverse man you shall show yourself perverse." Let us cleave, therefore, to the innocent and righteous, since these are the elect of God. Why are there strifes, and tumults, and divisions, and schisms, and wars among you? Have we not [all] one God and one Christ? Is there not one Spirit of grace poured out upon us? And have we not one calling in Christ? [Ephesians 4:4-6] Why do we divide and tear in pieces the members of Christ, and raise up strife against our own body, and have reached such a height of madness as to forget that "we are members one of another?" [Romans 12:5]

[AD 264] Dionysius of Alexandria on James 4:1
When a man has bought a large enough field and sees that his neighbor’s is larger still, he wants to increase his own so as to make his house greater.

[AD 614] Andreas of Caesarea on James 4:1
James shows that the teaching is not working, for they are all carnal and doing the most wicked things.

[AD 735] Bede on James 4:1
From where come wars and fights among you? Do they not come from this? That is, from jealousy and contention, which he previously forbade. Hence also here he more fully explains the same, adding:

And from your desires which wage war in your members, etc. Desires wage war in the members when the hands, or tongue, or the consent of other members intemperately obey the wicked suggestions of an evil mind. Concerning this, also in the earlier parts of this Epistle, he says: But each one is tempted by his own desire, being drawn away and enticed, etc. But desires for earthly goods can also be understood in this place, namely the desire for kingdoms, riches, honors, dignities. For because of these and similar innumerable things, fights and wars frequently arise among the wicked.

[AD 735] Bede on James 4:2
You quarrel and fight, and you do not have because you do not ask. You quarrel, he says, and fight for temporal glory, and you are not able to obtain this, precisely because you do not care to ask the Lord, so that he himself might bestow upon you whatever is beneficial. For if you were to ask him with pious intention, he would grant you both the earthly necessities for temporal use and the heavenly goods for eternal enjoyment.

[AD 990] Oecumenius on James 4:2
James proceeds here by way of thesis and antithesis. The thesis, that is, what they desire, is absurd to begin with, but the way they go about getting what they want ensures the exact opposite. Murder and fighting are not good things, but neither do the good things which they desire follow from them. Note also that here James speaks of murder and of fighting as spiritual things, not physical ones. It would be bad enough to think this kind of thing about robbers, but how much worse it is when we are dealing with people who have a certain amount of faith and who have turned to God. These are people who are trying to kill the soul and to fight against godliness.

[AD 398] Didymus the Blind on James 4:3
The Savior said: “Ask and you will receive. Everyone who asks will receive.” How can it be then that some people pray but do not get what they ask for? To this it must be answered that if someone comes to prayer in the right way, omitting none of the prerequisites for intercession, he will receive everything he asks for. But if someone appears to be going beyond the permissible bounds laid down for intercession, he will appear to be asking for something in the wrong way and therefore will not obtain it.

[AD 430] Augustine of Hippo on James 4:3
If someone intends to misuse what he receives, he will not receive it. Instead, God will pity him.

[AD 614] Andreas of Caesarea on James 4:3
It appears that some ask but do not receive. God ignores those who attack him and those who ask wrongly, according to their own desires. But someone will say that even those who ask for divine wisdom and virtue do not receive them. In reply it must be said that such people may be worthy to receive these good things, but they must do so in the right way. Perhaps they want such things merely for the pleasure of having them, and if so, they will not get them.

[AD 735] Bede on James 4:3
Those who continue in their sins ask wrongly. They entreat the Lord ill-advisedly to forgive them sins which they are not prepared to forgive in others.

[AD 735] Bede on James 4:3
You ask and do not receive, because you ask wrongly, etc. He had foretold that they do not ask, and now he says that they ask wrongly, because he who asks wrongly seems to ask nothing at all in the sight of the inner witness. He asks wrongly who, despising the Lord’s commands, desires supreme benefits from the Lord. He also asks wrongly who, having lost the love of higher things, seeks merely to gain lower goods, and this not for the sustenance of human frailty, but for the excess of unrestrained pleasure. This is indeed what he means when he says: So that you may spend it on your passions.

[AD 253] Origen of Alexandria on James 4:4
Since evil forms a friendship with the world and virtue a friendship with God, virtue and evil cannot coexist.

[AD 398] Didymus the Blind on James 4:4
Whoever loves the world by committing sin is revealed as an enemy of God, just as, on the other hand, one who affirms friendship with God by not sinning is a constant enemy of the world. Therefore, just as it is impossible to serve both God and mammon, so it is also impossible to be a friend of the world and of God at the same time.

[AD 430] Augustine of Hippo on James 4:4
It was because of these enmities toward God that not even his only-begotten Son was spared.

[AD 449] Hilary of Arles on James 4:4
Love of honor and pride and boastfulness is hostile to God, for these things were the undoing of the fallen angels as well as of the first human couple, which is why to this day they are described as “enemies of God.”

[AD 735] Bede on James 4:4
Adulterers, do you not know that friendship with this world is enmity with God? He rightly calls adulterers those whom, having turned from the love of heavenly wisdom to the embrace of worldly friendship, he reproaches, seeing that they serve mammon more than the Creator whom they despise. He had indeed spoken above about the manifest enemies of God: Do not the rich oppress you by their power, and do they not drag you to the courts? Do they not blaspheme the good name that has been invoked upon you (James II)? But lest you think that only those who openly blaspheme God, who persecute His faith in the saints, and unjustly condemn them are His enemies, he shows that those are also enemies of God who, under the faith and confession of the name of Christ, serve the lure and love of the world, who, only in name being faithful, set earthly things above heavenly ones. This he more earnestly enforces in the following verse, adding: Whoever therefore wishes to be a friend of this world constitutes himself an enemy of God. Therefore, all lovers of the world are enemies of God, all seekers of trifles, all who belong to those of whom it is said: Behold, your enemies, O Lord, shall perish (Psalm XCI). Whether they enter the churches or do not enter the churches, they are enemies of God. For a time they may flourish like grass, but when the heat of judgment appears, they will perish, and the beauty of their face shall fade.

[AD 990] Oecumenius on James 4:4
James calls these people adulterers, not because they practiced physical adultery but because they corrupted the commands which were instituted by God and turned away to other loves. They were even prepared to tolerate an adulterous teacher, even if it was clear that he was as deep in the mud as any pig.

[AD 1022] Symeon the New Theologian on James 4:4
When one is at enmity toward someone else, he has no idea how to explain to others what that person approves of or likes, nor is he able to instruct them concerning his desires.

[AD 425] Severian of Gabala on James 4:5
What this means is that the Spirit in us tends toward fellowship with God. He turns us away from the love of the world and gives us ever more grace.

[AD 735] Bede on James 4:5
Do you think that the Scripture says uselessly? Namely, that Scripture which, restraining the faithful from the society of evildoers, thus speaks through Moses: You shall not make a covenant with them, nor with their gods. They shall not live in your land, lest they make you sin against Me, for if you serve their gods, it will surely be a scandal to you (Exodus XXIII). And again: You shall not make their works, but you shall destroy them and break their statues (Ibid.).

Does the spirit that dwells within you desire to envoke envy? It should be read as a rhetorical question, as if he were saying: Does the Spirit of grace, with which you were marked on the day of redemption, desire this, that you should envy one another? Not, indeed, a good spirit in you, but an evil spirit causes the vice of envy. There is a similar mode of expression in the psalm: “A brother cannot redeem; a man shall redeem” (Psalm 48). For it is understood thus: If Christ, who deigned to become our brother through humanity, did not redeem us, could any mere human suffice to redeem us? Some interpret this passage thus: The spirit that dwells within you desires against envy—desiring, that is, that the sickness of envy be conquered and eradicated from your minds. Others understand it to refer to the human spirit, with the sense being: Do not covet, do not cling to the friendships of this world because the spirit of your mind, while it covets earthly things, indeed desires envy when you desire to acquire things for yourself, envying others who have them.

[AD 990] Oecumenius on James 4:5
James is here using an abbreviated form of speech in order to convey his meaning. What he is saying is this: “I have thus far been warning you in my own words to make the right and proper use of your wisdom that you might not abuse it in your pride by corrupting it or misinterpreting it by your overly clever preaching.”

[AD 99] Clement of Rome on James 4:6
Seeing, therefore, that we are the portion of the Holy One, let us do all those things which pertain to holiness, avoiding all evil-speaking, all abominable and impure embraces, together with all drunkenness, seeking after change, all abominable lusts, detestable adultery, and execrable pride. "For God," [says the Scripture], "resists the proud, but gives grace to the humble."

[AD 99] Clement of Rome on James 4:6
Scripture says that God resists the arrogant but gives grace to the humble. We should associate with those to whom God’s grace has been given.

[AD 108] Ignatius of Antioch on James 4:6
By this manifested his pride, and condemned himself. For it is written, "God resisteth the proud.".
"For he that yields not obedience to his superiors is self-confident, quarrelsome, and proud. But "God "says
[AD 215] Clement of Alexandria on James 4:6
There are those who say openly that marriage is fornication. They lay it down as a dogma that it was instituted by the devil. They are arrogant and claim that they are emulating the Lord, who did not marry and had no worldly possessions. It is their boast that they have a deeper understanding of the gospel than anyone else. To them Scripture says that God is against the proud and gives grace to the humble.

[AD 380] Apostolic Constitutions on James 4:6
We add, in the next place, that neither is every one that prophesies holy, nor every one that casts out devils religious: for even Balaam the son of Beor the prophet did prophesy, though he was himself ungodly; as also did Caiaphas, the falsely-named high priest... For neither is a wicked king any longer a king, but a tyrant; nor is a bishop oppressed with ignorance or an evil disposition a bishop, but falsely so called, being not one sent out by God, but by men... We say these things, not in contempt of true prophecies, for we know that they are wrought in holy men by the inspiration of God, but to put a stop to the boldness of vainglorious men; and add this withal, that from such as these God takes away His grace: for "God resists the proud, but gives grace to the humble." [1 Peter 5:5, James 4:6, Proverbs 3:34]

[AD 391] Macarius of Egypt on James 4:6
The true sign of a Christian is the following: to feed the hungry and give drink to the thirsty, to endure hunger and thirst, to be poor in spirit, humble and contemptible in one’s own eyes.

[AD 420] Jerome on James 4:6
One who holds his head high in arrogance hates God.

[AD 430] Augustine of Hippo on James 4:6
Give me someone professing perpetual continence, who is free from all vices and blemishes of conduct. For her I fear pride—I dread the swelling of self-conceit from so great a blessing. The more there is in her which she is satisfied with, the more I fear that in pleasing herself she will displease the one who resists the proud but gives grace to the humble.

[AD 460] Valerian of Cimiez on James 4:6
One man is invited to grace in proportion to his love of humility. Another is consigned to punishment in proportion to his sin of pride. So if the swelling of pride is taking place in anyone, let him combat it, lest he draw the arms of heavenly justice against himself.

[AD 542] Caesarius of Arles on James 4:6
Be humble, in order that God may rest in you, which he wants to do.

[AD 735] Bede on James 4:6
But He gives greater grace. The Lord gives greater grace than the friendship of the world, because while it provides these earthly goods temporarily and with the pain of losing them, He bestows eternal joy. He subsequently explains to whom He grants this grace.

For this reason it says: God resists the proud, but gives grace to the humble. Thieves, indeed, perjurers, the lustful, and other sinners are punished by God as despisers of His precepts, but He is said to resist the proud especially, because those who trust in their own virtue, who neglect to submit by repenting to divine power, who act as if they are sufficient to save themselves, and refuse to seek the aid of heavenly grace, are certainly afflicted with greater punishment. On the other hand, He gives grace to the humble, because those who submissively submit to the hands of the true physician in the wounds of their vices deservedly receive the gifts of the desired health. It is to be noted, however, that this statement regarding the proud and humble was placed by the blessed James from the proverbs of Solomon according to the ancient Translation, just as Peter did in his Epistle. In our Edition, which descends from Hebrew truth, it is said thus: He will mock the mockers, and He will give grace to the meek. The Lord will mock the mockers according to what Paul speaks about those who, refusing to receive Him coming in the name of His Father, will accept the Antichrist coming in his own name (John V): Because they did not receive the love of the truth that they might be saved, therefore God will send them strong delusion that they should believe a lie (Thess. II). He mocked the mockers when, to the Jews saying: If he is the king of Israel, let him come down from the cross and we will believe in him (Matt. XXVII), He patiently endured until, having died and been buried, He overcame their insults and even death itself by a swift resurrection. But He will give grace to the meek, because to those who humbly follow Him, He abundantly grants both the perfection of good work and the gifts of blessed eternity.

[AD 990] Oecumenius on James 4:6
It is not absurd to say that contempt for divine doctrine and an inordinate love for the world derive from pride and are the substance of enmity against God. God resists the proud, because it is normal to resist one’s enemies, and the proud must be counted among them.

[AD 542] Caesarius of Arles on James 4:7
Let us fight as hard as we can, with the Lord’s help, against that most harsh captivity of the soul [which is the devil’s ability to divert our thoughts away from spiritual concerns].

[AD 614] Andreas of Caesarea on James 4:7
If death came into the world by the malice of the devil, and Christ dwells in the inner man according to the Scriptures, this is the reason why he dwells in us, that he might destroy the death which has come upon us through the devil’s cunning. And not only this, but that he might give us more grace as well. For he said: “I have come that they might have life, and have it more abundantly.”

[AD 1963] CS Lewis on James 4:7
The more a man was in the Devil's power, the less he would be aware of it, on the principle that a man is still fairly sober as long as he knows he's drunk. It is the people who are fully awake and trying hard to be good who would be most aware of the Devil. It is when you start arming against Hitler that you first realize your country is full of Nazi agents. Of course, they don't want you to believe in the Devil. If devils exist, their first aim is to give you an anesthetic—to put you off your guard. Only if that fails, do you become aware of them.

[AD 397] Ambrose of Milan on James 4:8
God is near, and he does not drive away those who draw near to him.

[AD 735] Bede on James 4:8
Draw near to God, and He will draw near to you: Draw near to the Lord by following His footsteps in humility, and He will draw near to you through mercy, freeing you from distress. For no one is far from God in terms of regions, but in terms of affections. Indeed, dwelling in one place on earth, both he who is diligent in virtues and he who wallows in the filth of vices, one is far from God, the other has God near. Hence the Psalmist says: "The Lord is near to all who call upon Him in truth" (Psalm 145). Again: "Salvation is far from sinners" (Psalm 119). That same salvation of which we sing: "The Lord is my light and my salvation, whom shall I fear?" (Psalm 27). And the Lord Himself, when He encouraged us to draw near to Him by saying: "Come to Me, all who labor and are heavy laden, and I will give you rest" (Matthew 11), immediately demonstrated that this should be fulfilled not by feet but by actions when He added: "Take My yoke upon you, and learn from Me, for I am gentle and humble in heart" (ibid.).

Cleanse your hands, you sinners, and purify your hearts, you double-minded. This is truly to draw near to the Lord, namely to have purity of works and simplicity of heart. "Innocent," he says, "with clean hands and a pure heart, this one shall receive a blessing from the Lord, and mercy" (Psalm 25). And this is truly the Lord drawing near to us, to give to us simply those gifts of His mercy which we seek. For the Holy Spirit of discipline will flee deceit, and will withdraw from thoughts that are without understanding (Wisdom 1).

[AD 990] Oecumenius on James 4:8
James describes as double-minded those who do not want to live in a committed way but who are tossed about by the iniquities of men. It is clear from what Job says that the mind here stands for our very life: “skin for skin,” [Satan says], “all that a man has he will give for his own soul.”

[AD 407] John Chrysostom on James 4:9
The person who repents after sinning is worthy of blessings, not of mourning, as he returns to the company of the righteous. First, confess your sins that you may be justified, for if someone is not ashamed of his sin he is miserable, not so much because he fell from grace but because he has remained in his fallen state. And if it is a wicked thing not to repent after sinning, what punishment will someone deserve who sins as a matter of course? If a person overcome with the need to repent is unclean, what forgiveness will there be for someone who suffers because he remains in his sins?

[AD 601] Leander of Seville on James 4:9
Flee laughter as a sin and change temporal joy into mourning so that you may be blessed, for those who mourn are blessed and shall be comforted.

[AD 735] Bede on James 4:9-10
Be miserable, mourn and weep. Let your laughter be turned to mourning and your joy to gloom. Humble yourselves in the presence of the Lord, and He will exalt you. Do not, He says, love to become wealthy and rejoice in this world, but being mindful of the sins you have committed, rather aim that through the brief miseries, poverty and transient lamentation of this life you may reach the eternal joys of the heavenly kingdom, so that you do not, for the temporary joy of wealth which you have acquired through unjust labor, perpetually beg, mourn, and pay the penalties in torment.

[AD 398] Didymus the Blind on James 4:10
Pride is the greatest of all evils. To the extent that humility can oppose it, it is a great good. And when both of these are consciously and deliberately at work, good I mean and evil, everyone who humbles himself before God and rejects the proud will be raised up, and his humility will take him to the heights.

[AD 450] Hesychius of Jerusalem on James 4:10
It is a blessed thing to humble oneself before the Lord. For James says: “Humble yourselves before the Lord, and he will exalt you.” Whenever we are thus humbled, even if we are tempted by demons and even if we are attacked by those who hate virtue, we have God to deliver us, as long as we do not forget his law or curse him in our sufferings.

[AD 444] Cyril of Alexandria on James 4:11
Every wicked act dulls the sense of our thoughts and gives birth to arrogance. For although it is necessary for each one to examine himself and behave according to God’s will, many people do not do this but prefer to mind the business of others. If they happen to see others suffering, it seems that they forget their own weaknesses and set about criticizing them and slandering them. They condemn them, not knowing that they suffer from the same things as the people they have criticized, and in so doing they condemn themselves. The wise Paul writes exactly the same thing: “If you judge another in something, you condemn yourself, for the one who judges does the same things.”

[AD 735] Bede on James 4:11
Do not slander one another, my brothers. This vice of slander looks to the deadly venom of the tongue, about which it is said: You quarrel and fight.

He who slanders a brother or judges his brother, slanders the law and judges the law. He slanders the law who slanders a brother, as if it were not right for it to have forbidden slander, saying through the Prophet: "I pursued the one who secretly slanders his neighbor" (Psalm 101). And in Leviticus: "You shall not be a slanderer, nor a whisperer among the people" (Leviticus 19). It can also be understood this way: He who slanders a brother who is obeying the law, slanders the law and judges the law that gave such commands. For instance, the law commanded, saying: "You shall not remember the wrongs of your fellow citizens." Therefore, he who slanders a brother and judges a brother whom he sees willingly accepting injuries for the love of God, certainly slanders the law and judges the law that commanded us to forget wrongs.

[AD 990] Oecumenius on James 4:11
James knows that haughtiness and pride arise from contempt and disdain toward the meek, which pushes those who behave that way to despise them completely. He wants to turn his hearers aside from this.

[AD 449] Hilary of Arles on James 4:12
The law of the Bible was given through many agents, like Moses and Elijah and John the Baptist, but ultimately it is still only one law, and there is only one lawgiver.

[AD 735] Bede on James 4:12
But who are you to judge your neighbor? He condemns the recklessness of the one who delights in judging his neighbor without taking care to consider the state of his own frailty and the uncertainties of his temporal life. And because sometimes, through the change of the right hand of the Most High, those who judged their neighbor are subjected to the power of the one they judged, sometimes they are suddenly taken from the world while still living, he subsequently also condemns the recklessness of those who, having no certainty of their own life, stretch their minds into the future, thinking of the profits of many years to come.

[AD 1107] Theophylact of Ohrid on James 4:12
Who would endure having to live under a law which he despises? Therefore do not be a despiser of the law, says James, and do not look for some other legislator, who will prescribe the opposite. For there is only one lawgiver, God, who can both condemn and deliver sinners.

[AD 444] Cyril of Alexandria on James 4:13
Some people go on endless journeys for the sake of business and the profits which they can make thereby, enduring even sea travel for their sake. Some fight in order to get some advantage over others by increasing their power. Still others fatten their purses by cheating and by extortion, bringing down fire and brimstone on their heads.

[AD 735] Bede on James 4:13
Behold now, you who say: "Today or tomorrow we will go into such a city, and spend a year there, and trade, and make a profit," yet you do not know what tomorrow will bring. He notes the folly in this kind of planning in many ways, since clearly they both consult about the increase of profit and assume they will live for a long time, and that it is within their power to spend a year there, and in all of these things they disdain to recall the judgment of the Supreme Judge to mind.

[AD 990] Oecumenius on James 4:13
James does not take away our free will but points out that everything we do is part of a wider plan which is governed by God’s grace. Even if we are able to run around and get on with the business of this life, we must not attribute this ability to our own efforts but accept that we can do these things only by the blessing of God.

[AD 430] Augustine of Hippo on James 4:14
Restoring health for a time to a man’s body amounts to no more than extending his breath for a little while longer. Therefore it should not be considered of great importance, because it is temporal, not eternal.

[AD 735] Bede on James 4:14
For what is your life? It is a vapor that appears for a little while and then vanishes away. He does not say what is our life, but what, he says, is your life? Because the righteous truly begin to live when they reach the end of this life. But the enemies of the Lord, when they have been honored and exalted, will perish like smoke (Psalm 36). However, it should not be thought that this is the same sentiment which the ungodly are reported to have expressed in the book of Wisdom: For we are born from nothing, and after this we will be as though we had never been (Wisdom 2). Because smoke has been blown into our nostrils, and a word as a spark to stir up our heart. When this is extinguished, the body will be ashes, and the spirit will be dispersed like soft air. For these things reasoned with those who believed in no life except this one, saying with Epicurus: “After death there is nothing, and death itself is nothing.” But the blessed James added that the life of the wicked is short in the present, yet in the future, eternal death follows, according to the saying of the blessed Job: They spend their days in wealth, and in a moment go down to the grave (Job 21).

[AD 990] Oecumenius on James 4:14
James says this in order to indicate just how fleeting and empty our present life is. He wants to make us ashamed of the fact that we spend all our time engaged in its vanity, and in the evils of this age and in things which, as soon as they are accomplished, disappear, and all our labor vanishes with them.

[AD 407] John Chrysostom on James 4:15
James is not trying to take away our freedom to decide, but he is showing us that it is not just what we want that matters. We need God’s grace to complement our efforts and ought to rely not on them but on God’s love for us. As it says in Proverbs: “Do not boast about tomorrow, for you do not know what a day may bring forth.”

[AD 990] Oecumenius on James 4:16
Vain boasting comes from pride, and its ultimate source is the devil. Those who have been baptized into Christ ought not to take any kind of inspiration from Satan.

[AD 407] John Chrysostom on James 4:17
James does not remove the power to do good, but he shows that it is not just a matter of one’s own will. To do good as we ought, we need the grace of God.

[AD 430] Augustine of Hippo on James 4:17
Does the one who does not know how to do good and does not do it commit a sin? He certainly does, but the one who knows what is good and does not do it sins more grievously.

[AD 735] Bede on James 4:17
To him therefore who knows to do good and does not do it, it is sin. Throughout the text of this Epistle, the blessed James shows that those to whom he wrote had the knowledge of doing good, and had also learned the right faith, so that they had presumed they could become teachers to others, yet had not attained the perfection of works, or humility of mind, or even moderation of speech. Hence, he now among other words of reproof and exhortation greatly frightens them with this statement, that he who knows how to do good, and does not do what he knows, is said to have a greater sin than he who sins out of ignorance. Although he who sins in ignorance cannot be entirely free from guilt, for ignorance of good itself is not a small evil. Hence the Lord said: The servant who knew his master’s will, and did not prepare himself or do according to his will, shall be beaten with many stripes. But he who did not know, yet committed things deserving of stripes, shall be beaten with few (Luke 12).

[AD 990] Oecumenius on James 4:17
Good deeds ought to come before preaching, so that it will be clear that it is a righteous man who is proclaiming the faith which is being expounded.