33 He that hath received his testimony hath set to his seal that God is true.
[AD 215] Clement of Alexandria on John 3:33
Wherefore the Father bestows on him the glory and honour that was due and meet, putting on him the best robe, the robe of immortality; and a ring, a royal signet and divine seal, — impress of consecration, signature of glory, pledge of testimony (for it is said, "He has set to his seal that God is true,") [John 3:33] and shoes, not those perishable ones which he has set his foot on holy ground is bidden take off, nor such as he who is sent to preach the kingdom of heaven is forbidden to put on, but such as wear not, and are suited for the journey to heaven, becoming and adorning the heavenly path, such as unwashed feet never put on, but those which are washed by our Teacher and Lord.

[AD 407] John Chrysostom on John 3:33
(Hom. xxx. 2) i. e. hath shown that God is true. This is to alarm them: for it is as much as saying, no one can disbelieve Christ without convicting God, Who sent Him, of falsehood: inasmuch as He speaks nothing but what is of the Father.

[AD 407] John Chrysostom on John 3:33
"He that hath received His testimony hath set to his seal that God is true." Here he terrifies them also by showing that he who believeth not on Him, disbelieveth not Him alone, but the Father also; wherefore he adds: "He whom God hath sent speaketh the words of God."

Since then He speaketh His words, he that believeth and he that believeth not, believeth or believeth not God. "Hath set to His seal," that is, "hath declared." Then, to increase their dread, he saith, "that God is true;" thus showing, that no man could disbelieve Christ without making God who sent Him guilty of a falsehood. Because, since He saith nothing save what is from the Father, but all that He saith is His, he that heareth not Him, heareth not Him that sent Him. See how by these words again he strikes them with fear. As yet they thought it no great thing not to hearken to Christ; and therefore he held so great a danger above the heads of the unbelievers, that they might learn that they hearken not to God Himself, who hearken not to Christ.

[AD 430] Augustine of Hippo on John 3:33
"He that cometh from heaven is above all; and what He hath seen and heard, that testifieth He; and His testimony no man receiveth." If no man, to what purpose came He? He means, no man of a certain class. There are some people prepared for the wrath of God, to be damned with the devil; of these, none receiveth the testimony of Christ. For if none at all, not any man, received, what could these words mean, "But he that received His testimony hath set to his seal that God is true"? Not certainly, then, no man, if thou sayest thyself, "He that received His testimony has set to his seal that God is true." Perhaps John, on being questioned, would answer and say, I know what I have said, in saying no man. There are, in fact, people born to God's wrath, and thereunto foreknown. For God knows who they are that will and that will not believe; He knows who they are that shall persevere in that in which they have believed, and who that shall fall away; and all that shall be for eternal life are numbered by God; and He knows already the people set apart. And if He knows this, and has given to the prophets by His Spirit to know it, He gave this also to John. Now John was observing, not with his eye, - for as regards himself he is earth, and speaketh of earth, - but with that grace of the Spirit which he received of God, he saw a certain people, ungodly, unbelieving. Contemplating that people in its unbelief, he says, "His testimony, who came from heaven, no man receiveth." No man of whom? Of them who shall be on the left hand, of them to whom it shall be said, "Go into the everlasting fire, which is prepared for the devil and his angels." Who are they that do receive it? They who shall be at the right hand, they to whom it shall be said, "Come, ye blessed of my Father, receive the kingdom which is prepared for you from the beginning of the world." He observes, then, in the Spirit a dividing, but in the human race a mingling together; and that which is not yet separated locally, he separated in the understanding, in the view of the heart; and he saw two peoples, one of believers, one of unbelievers. Fixing his thought on the unbelievers, he says, "He that cometh from heaven is above all; and what He hath seen and heard, that He testifieth and no man receiveth His testimony." He then turned his thought from the left hand, and looked at the right, and proceeded to say, "He that received His testimony has set to his seal that God is true." What means "has set to his seal that God is true," if it be not that man is a liar, and God is true? For no human being can speak any truth, unless he be enlightened by Him who cannot lie. God, then, is true; but Christ is God. Wouldest thou prove this? Receive His testimony and thou findest it. For "he that hath received His testimony has set to his seal that God is true." Who is true? The same who came from heaven, and is above all, is God, and true. But if thou dost not yet understand Him to be God, thou hast not yet received His testimony: receive it, and thou puttest thy seal to it; confidently thou understandest, definitely thou acknowledgest, that God is true.

[AD 430] Augustine of Hippo on John 3:33
(Tr. xiv. c. 8) Or thus; There is a people reserved for the wrath of God, and to be condemned with the devil; of whom none receiveth the testimony of Christ. And others there are ordained to eternal life. Mark how mankind are divided spiritually, though as human beings they are mixed up together: and John separated them by the thoughts of their heart, though as yet they were not divided in respect of place, and looked on them as two classes, the unbelievers, and the believers. Looking to the unbelievers, he saith, No man receiveth his testimony. Then turning to those on the right hand he saith, He that hath received his testimony, hath set to his seal.

(Tr. xiv. c. 8) What is it, that God is true, except that God is true, and every man a liar? For no man can say what truth is, till he is enlightened by Him who cannot lie. God then is true, and Christ is God. Wouldest thou have proof? Hear His testimony, and thou wilt find it so. But if thou dost not yet understand God, thou hast not yet received His testimony.

[AD 444] Cyril of Alexandria on John 3:33
CHAPTER III. That Christ is God and of God by Nature.

In no other way was it possible to sho the impiety of them that believe not, except the glorious achievement of the believers were made known. For by the contrast of good things is the evil easily discerned, and the knowledge of what is better convicts the worse. If any then (saith he) have assented to the words of Him That cometh from above, he hath sealed and confirmed by his understanding, that truth is ever akin and most dear to the Divine Nature. Whence the converse is manifest to them that see. For he who thrusts away the faith will surely witness against himself, that God is not true. But we must again take notice, that he removes the Son from consubstantiality with the creation, and shows by what has been said that He is by Nature God. For if he that believeth the things spoken by Him, and receiveth the testimony which He gave of Himself, sealed and well confirmed that God is true; how shall not Christ be conceived of as by Nature God, Who is testified of as true by the credit of the things just said? or let our opponent again say how the Divine Nature is honoured, as being true, by our Saviour's testimony being received. For if He be not wholly by Nature God, he that believeth will not be reverencing the Divine Nature, as true, but rather one (according to them) the fairest of creatures. But since, when Christ is believed, the declaration of being true extendeth to God, it is I suppose altogether clear, that He being God, not falsely so called, Himself taketh honour to Himself from those who believe. |191

But the enemy of the truth will not (it seems) agree to these words of ours, but will start up strong, not admitting the Son to be by Nature God: and will say again, Thou cavillest, sir, and contrivest turns of many-varied reasonings, ever rejecting somehow the simple and right sense. For since the Word of God hath come down from Heaven, calling out openly, I speak not of Myself, but the Father Which sent Me, He gave Me a commandment, what I should say and what I should speak: and again, All things that I have heard of My Father, I will make known unto you: or also, as the holy Baptist averred in the following words, For He Whom God hath sent speaketh the words of God: therefore of Him is he saying, He that receiveth His testimony hath set to his seal, that God is True. For verily is God the Father true, but thou attemptest to bring round to the Son what is due to Another.

What then shall we say to these things? shall we class the Only-Begotten among the prophets, fulfilling the ministry befitting Prophets, and doing nought besides? For by whom is it not unhesitatingly received, that Prophets used to bring us voices from God? Then what excellence is there in the Son, if He accomplish this alone? how is He above all, if He is still ranked along with Prophets, and is clad in slave-befitting measure? How, as though surpassing them in glory doth He say in the Gospels, If He called them gods unto whom the Word of God came, and the Scripture cannot be broken, say ye of Him Whom the Father hath sanctified and sent into the world, Thou blasphemest: because I said, I am the Son of God? For in these words He clearly severeth Himself off from the company of Prophets, and saith that they were called gods, because the Word of God came to them, but Himself He con-fesseth Son. For to the holy Prophets was imparted grace by measure through the Spirit; but in our Saviour Christ it hath pleased all the full ness of the God-head to dwell bodily, as Paul saith; wherefore also of His fullness have all we received, as John affirmed. How then will the Giver be On a par with the recipients, or how will the Fullness of the God-head be reckoned in the portion of the minister?

Let them then hence consider narrowly, into how great blasphemy their argument will hazard them. And how one ought to understand the words, I speak not of Myself, but the Father Which sent Me, He gave Me a commandment what I should say and what I should speak, will be explained more at large in its proper time and place. But I think that at present the objections of our opponents ought to be made a foundation of piety, and from what they put forth, we ought to contend for the doctrines of the Church. They then affirm that the Son has received commandments from the Father, and says nothing of Himself: but whatsoever He heard, as Himself says, these things He is zealous to say to us too. Well, let him hold to this; for we will agree, since this nothing wrongeth the Son, as far at least as concerns the question of whence He is; yea rather it bringeth in a most beautiful ceconomy in respect of the present subject. Therefore when they hear Him say, I and the Father are One; He that hath seen Me hath seen the Father; I am in the Father, and the Father in Me: let them receive His testimony, let them set to their seal, that God the Father is true, persuading the Son to speak what He knoweth accurately; let them not disbelieve the words of the Saviour, interpreting to us the things of His Father.

[AD 444] Cyril of Alexandria on John 3:33
There was no other possible way of showing the impiety of those who do not believe except by making known the glorious achievement of the believers. Evil is a lot easier to see when it is contrasted with good. When you know there is something better out there, it only puts what is worse in starker contrast. If anyone then, John says, has assented to the words of the one who comes from above, he has sealed and confirmed by his understanding that truth is ever near and dear to the divine nature. The opposite is just as obvious because anyone who throws away the faith will most certainly testify, against himself, that God is not true.

[AD 804] Alcuin of York on John 3:33
Or, Hath put to his seal, i. e. hath put a seal on his heart, for a singular and special token, that this is the true God, Who suffered for the salvation of mankind.