20 Verily, verily, I say unto you, He that receiveth whomsoever I send receiveth me; and he that receiveth me receiveth him that sent me.
[AD 253] Origen of Alexandria on John 13:20
Whomever the Savior sends to minister to the salvation of anyone, that person who is sent is an apostle of Jesus Christ. But just as the apostle is an apostle of the one who sent him, so is he an apostle only to those to whom he is sent.

[AD 253] Origen of Alexandria on John 13:20
He who receives whom[ever] Jesus may send, receives Jesus in the one sent, and he who receives Jesus receives the Father. Therefore, he who receives whomever Jesus may send receives the Father who sent Jesus.

[AD 380] Apostolic Constitutions on John 13:20
For says the Lord: "He that heareth you, heareth me; and he that heareth me, heareth Him that sent me. "And, "He that despiseth you, despiseth me; and he that despiseth me, despiseth Him that sent me."

[AD 407] John Chrysostom on John 13:12-20
(Hom. lxxi. 1) He speaks now not to Peter alone, but to all: Ye call Me Master and Lord. He accepts their judgment; and to prevent the words being set down merely to favour on their parts, adds, And ye say well, for so I am.

(Hom. lxx. 1) He shows us the greater, that we may do the less. For He was the Lord, but we, if we do it, do it to our fellow-servants: For I have given you an example, that ye should do as I have done to you.

(Hom. lxxi. 2) He continues to urge them to wash one another's feet; Verily, verily, I say unto you, The servant is not greater than his lord, neither He that is sent greater than He that sent Him; as if to say, If I do it, much more ought you.

(Hom. Lxxi. 2) For all know, but all do not do. He then rebukes the traitor, not openly, but covertly: I speak not of you all.

(Hom. lxxi. 1) Then, that He might not sadden them all, He adds, But that the Scripture must be fulfilled, He that eateth bread with Me, hath lifted up his heel against Me: showing that He knew who the traitor was, an intimation that would surely have checked him, if any thing would. He does not say, shall betray Me, but, shall lift up his heel against Me, alluding to his deceit and secret plotting.

(Hom. lxxi. 2) He that eateth bread with Me; i. e. who was fed by Me, who partook of My table. So that if injured ever by our servants or inferiors, we need not be offended. Judas had received infinite benefits, and yet thus requited his Benefactor.

(Hom. Lxxii. 3) As the disciples were about to go forth and to suffer many things, He consoles them by promising His own assistance and that of others; His own, when He says, Happy are ye if ye do them; that of others, in what follows, Verily, verily, I say unto you, He that receiveth whomsoever I send, receiveth Me; and he that receiveth Me receiveth Him that sent Me.

[AD 407] John Chrysostom on John 13:12-20
Now when He had washed their feet, and taken His garments, and sat down, He said, "Know ye what I have done unto you?" He no longer addresseth Himself to Peter only, but to them all.

"Ye call Me Lord and Master, and ye say well, for so I am."

"Ye call Me." He taketh to Him their judgment, and then that the words may not be thought to be words of their kindness, He addeth, "for so I am." By introducing a saying of theirs, He maketh it not offensive, and by confirming it Himself when introduced from them, unsuspected. "For so I am," He saith. Seest thou how when He converseth with the disciples, He speaketh revealing more what belongeth unto Himself?

[AD 407] John Chrysostom on John 13:12-20
"If I then," He saith, "your Lord and Master have washed your feet, ye ought also to wash one another's feet. For I have given you an example, that ye should do as I have done to you."

And yet it is not the same thing, for He is Lord and Master, but ye are fellow-servants one of another. What meaneth then the "as"? "With the same zeal." For on this account He taketh instances from greater actions that we may, if so be, perform the less. Thus schoolmasters write the letters for children very beautifully, that they may come to imitate them though but in an inferior manner. Where now are they who spit on their fellow-servants? where now they who demand honors? Christ washed the feet of the traitor, the sacrilegious, the thief, and that close to the time of the betrayal, and incurable as he was, made him a partaker of His table; and art thou highminded, and dost thou draw up thine eyebrows?

[AD 407] John Chrysostom on John 13:12-20
"Let us then wash one another's feet," saith some one, "then we must wash those of our domestics." And what great thing if we do wash even those of our domestics? In our case "slave" and "free" is a difference of words; but there an actual reality. For by nature He was Lord and we servants, yet even this He refused not at this time to do. But now it is matter for contentment if we do not treat free men as bondmen, as slaves bought with money. And what shall we say in that day, if after receiving proofs of such forbearance, we ourselves do not imitate them at all, but take the contrary part, being in diametrical opposition, lifted up, and not discharging the debt? For God hath made us debtors one to another, having first so done Himself, and hath made us debtors of a less amount. For He was our Lord, but we do it, if we do it at all, to our fellow-servants, a thing which He Himself implied by saying, "If I then your Lord and Master-so also do ye." It would indeed naturally have followed to say, "How much more should ye servants," but He left this to the conscience of the hearers.

[AD 407] John Chrysostom on John 13:12-20
But why hath He done this "now"? They were for the future to enjoy, some greater, some less honor. In order then that they may not exalt themselves one above the other, and say as they did before, "Who is the greatest," nor be angry one against the other, He taketh down the high thoughts of them all, by saying, that "although thou mayest be very great, thou oughtest to have no high thoughts towards thy brother." And He mentioned not the greater action, that "if I have washed the feet of the traitor, what great matter if ye one another's?" but having exemplified this by deeds, He then left it to the judgment of the spectators.

[AD 407] John Chrysostom on John 13:12-20
"Verily I say unto you, the servant is not greater than his lord, neither he that is sent greater than he that sent him. If ye know these things, happy are ye if ye do them. I speak not of you all - but that the Scripture may be fulfilled, He that eateth bread with Me hath lifted up his heel against Me."

What He said before, this He saith here also, to shame them; "For if the servant is not greater than his master, nor he that is sent greater than him that sent him, and these things have been done by Me, much more ought they to be done by you." Then, lest any one should say, "Why now sayest Thou these things? Do we not already know them?" He addeth this very thing, "I speak not to you as not knowing, but that by your actions ye may show forth the things spoken of." For "to know," belongeth to all; but "to do," not to all. On this account He said, "Blessed are ye if ye do them"; and on this account I continually and ever say the same to you, although ye know it, that I may set you on the work. Since even Jews "know," but yet they are not "blessed"; for they do not what they know.

[AD 407] John Chrysostom on John 13:12-20
"I speak not," He saith, "of you all." O what forbearance! Not yet doth He convict the traitor, but veileth the matter, hence giving him room for repentance. He convicteth and yet doth not convict him when He saith thus, "He that eateth bread with Me hath lifted up his heel against Me." It seems to me that the, "The servant is not greater than his lord," was uttered for this purpose also, that if any persons should at any time suffer harm either from domestics or from any of the meaner sort, they should not be offended; looking to the instance of Judas, who having enjoyed ten thousand good things, repaid his Benefactor with the contrary. On this account He added, "He that eateth bread with Me," and letting pass all the rest, He hath put that which was most fitted to restrain and shame him; "he who was fed by Me," He saith, "and who shared My table." And He spake the words, to instruct them to benefit those who did evil to them, even though such persons should continue incurable.

[AD 407] John Chrysostom on John 13:12-20
But having said, "I speak not of you all," in order not to attach fear to more than one, He at last separateth the traitor, speaking thus; "He that eateth bread with Me." For the, "not of you all," doth not direct the words to any single one, therefore He added, "He that eateth bread with Me"; showing to that wretched one that He was not seized in ignorance, but even with full knowledge; a thing which of itself was most of all fitted to restrain him. And He said not, "betrayeth Me," but, "hath lifted up his heel against Me," desiring to represent the deceit, the treachery, the secrecy of the plot.

[AD 407] John Chrysostom on John 13:20
Great is the recompense of care bestowed upon the servants of God, and of itself it yieldeth to us its fruits. For, "he that receiveth you," it saith, "receiveth Me, and he that receiveth Me, receiveth Him that sent Me." Now what can be equal to the receiving Christ and His Father? But what kind of connection hath this with what was said before? What hath it in common with that which He had said, "If ye do these things happy are ye," to add, "He that receiveth you"? A close connection, and very harmonious. Observe how. When they were about to go forth and to suffer many dreadful things, He comforteth them in two ways; one derived from Himself, the other derived from others. "For if," He saith, "ye are truly wise, ever keeping Me in mind, and bearing about all both what I said, and what I did, ye will easily endure terrible things. And not in this way only, but also from your enjoying great attention from all men." The first point He declared when He said, "If ye do these things happy are ye"; the second when He said, "He that receiveth you receiveth Me." For He opened the houses of all men to them, so that both from the sound wisdom of their manners, and the zeal of those who would tend them, they might have twofold comfort.

[AD 430] Augustine of Hippo on John 13:20
(Tr. xlix. 2) The Arians, when they hear this passage, appeal immediately to the gradations in their system, that as far as the Apostle is from the Lord, so far is the Son from the Father. But our Lord hath left us no room for doubt on this head; for He saith, I and My Father are one. (supr. 10:30) But how shall we understand those words of our Lord, He that receiveth Me, receiveth Him that sent Me? If we take them to mean that the Father and the Son are of one nature, it will seem to follow, when He says, He that receiveth whomsoever I send, receiveth Me, that the Son and an Apostle are of one nature. May not the meaning be, He that receiveth whosoever I send, receiveth Me, i. e. Me as man: But He that receiveth Me, i. e. as God, receiveth Him that sent Me. But it is not this unity of nature, which is here put forth, but the authority of the Sender, as represented by Him who is sent. In Peter hear Christ, the Master of the disciple, in the Son the Father, the Begotten of the Only Begotten.

[AD 430] Augustine of Hippo on John 13:20
He then proceeds to say: "Verily, verily, I say unto you, He that receiveth whomsoever I send, receiveth me; and he that receiveth me, receiveth Him that sent me." Did He mean us to understand that there is as little distance between one sent by Him, and Himself, as there is between Himself and God the Father? If we take it in this way, I know not what measurements of distance we shall be adopting, in the Arian fashion. For they, when they hear or read these words of the Gospel, have immediate recourse to their dogmatic measurements, whereby they ascend not to life, but fall headlong into death. For they straightway say: The Son's messenger stands at the same relative distance from the Son, as expressed in the words, "He that receiveth whomsoever I send, receiveth me," as that in which the Son Himself stands from the Father, when He said, "He that receiveth me, receiveth Him that sent me." But if thou sayest so, thou forgettest, heretic, thy measurements. Restrain, therefore, your foolhardy presumption; and do not be seeking to find in these words the same distance between the Son and His messenger as between the Father and His Son. But listen rather to the Son Himself, when He says, "I and my Father are one." For there the Truth hath left you no shadow of distance between the Begetter and the Only-begotten; there Christ Himself hath erased your measurements, and the rock hath broken your staircase to pieces.

But now that the heretical slander has been disposed of, in what sense are we to understand these words of the Lord: "He that receiveth whomsoever I send, receiveth me; and he that receiveth me, receiveth Him that sent me"? For if we were inclined to understand the words, "He that receiveth me, receiveth Him that sent me," as expressing the oneness in nature of the Father and the Son; the sequence from the similar arrangement of words in the other clause, "He that receiveth whomsoever I send, receiveth me," would be the unity in nature of the Son and His messenger. But it is not this unity of nature which the Lord intended to commend in this sentence, but the authority of the Sender in Him who is sent. Let every one, therefore, so receive Him that is sent, that in His person he may give heed to Him who sent Him. If, then, thou lookest for Christ in Peter, thou wilt find the disciple's instructor; and if thou lookest for the Father in the Son, thou wilt find the Begetter of the Only-begotten: and so in Him who is sent, thou art not mistaken in receiving the Sender.

[AD 444] Cyril of Alexandria on John 13:20
Having previously shown in a manner suitable to the occasion that He is the Christ, and having indicated the means by which the traitor was meditating his grievous outrage against Him, He now devises another very effectual method for overthrowing his evil designs. And now again His discourse seems to be marked by a certain want of distinctness: for He is still trying to conceal the daring deed, and as yet does not openly say who is about to betray Him. He proves therefore, and that very effectually by a clear illustration, that it is absolutely necessary to consider the Person of God the Father as included in the object of the love and reverence shown to Himself. And yet the main object that He wishes here to demonstrate is surely not this, but rather perhaps in my opinion exactly the converse. For leaving, as seems probable, the plainer [negative] form of speech, which He used at other times,----as for example in the words: He that honoureth not the Son honoureth not the Father,----He has here passed to the milder [positive] form of expression, intending all the while that His hearers should from this infer the converse. For surely it was a time for threatening rather than for exhortation, when the deed was already at the doors, and when the grievous outrage against Him was already in course of preparation. For Satan had already planted the evil design in the heart of the traitor. "As therefore," He says, "a man would certainly acknowledge Me in My own person and not another, if he received one who had been sent by Me; even so he that received One sent forth by God the Father would in all likelihood receive the Father Himself." But in these words of Christ any one may perceive the meaning indicated, seeing through the mildness of the language. And turning the statement into its converse, the traitor's impiety will be seen to be a transgression, not only against the Son, but also against even the Father Himself. The language used is therefore a form of threatening, though couched in somewhat mild terms; and it conveys the same idea that words of foreboding would properly suggest. For even as one among ourselves will receive one sent by God, assenting to the words he speaks, and paying honour to the God of Whom he preaches by observing the Divine oracles he proclaims; on just the same grounds I think one would receive the Lord, and through Him the Father, by believing on the Son. For the manifestation of the parent is ever the natural office of the offspring. So he who has fully believed that Christ is the Son thereby fully confesses the God Who begat the Son. Terrible therefore is the sentence pronounced on the traitor, since his rebellious insult is even against God the Father, because so much is involved in his impious outrage against the Son. For if with unswerving faith he had acknowledged the Son to be God of God, he would then have accepted and reverenced Him, submitting heart and soul in sincerity to Him as to the Lord; and then would the wretched man have found his love to Christ stronger than base passions, nor methinks would he, by being found guilty of treachery, have made it true concerning himself that it would have been better for him if he had never at all been born.

[AD 1107] Theophylact of Ohrid on John 13:20
What is the connection of the present words with the preceding ones? For until now He was speaking about the betrayer, and now He adds "he who receives whomever I send receives Me"? The connection exists, and it is the closest one.
The Lord said that He would be betrayed; He spoke of how He would leave them, that they would afterwards scatter, be dispersed, and endure many afflictions; therefore He comforts them in two ways. First, through Himself. For He showed them what He Himself would suffer, and what He did for the betrayer, washing his feet and admitting him to partake at the table. For if they keep this in mind, they will easily endure any afflictions. So then, the first way consists in this: that the Lord comforts them by what He did for the enemy, healing him to the very end, and by what He Himself would suffer.
Another way is that He opens the homes of all people for them, that all who hear their teaching will receive them. Do you see the connection of the present words with the preceding ones? The Lord will leave them; they will endure a multitude of evils and afflictions; He comforted them by His own example, for He would be betrayed by a disciple, yet He washes his feet; He also comforts them by foretelling that although they will experience many afflictions, all will receive them. He who receives you receives Me, and through Me, God and the Father. Note the power of the consolation. "You," He says, "people will honor as God Himself; therefore do not be disheartened by the malice of persecutors."

[AD 1274] Thomas Aquinas on John 13:20
Next (v 20), he confirms his conclusion from the dignity of those whose feet he washed. For their dignity was so great that services performed for them seemed in a way to rebound to God, although according to a certain progression: because things done for the faithful through Christ rebound to God the Father.

First, he shows how those things done for the disciples of Christ flow back or rebound to Christ. Regarding this he says, Truly, truly, I say to you. He is saying in effect: Truly, you ought to wash their feet, because he who receives any one whom I send receives me, that is, I regard as done to me the service given to those whom I send: "He who receives you receives me" (Mt 10:41). Secondly, he shows how a service given to Christ rebounds to the Father, saying, he who receives me receives him who sent me: "That all may honor the Son, even as they honor the Father" (5:23).

However, according to Origen, this verse can be understood in two ways. In one way by compressing the two parts into one, and then the sense is: he who receives those sent by me also receives the Father. The second way keeps the parts distinct, and then the meaning is: he who receives, that is, in a physical way, those sent by me, receives me; and those who receive me, that is, coming into their souls in a spiritual way - as in "that Christ may dwell in your hearts through faith" (Eph 3:17) - receives him who sent me, the Father. Not only will I dwell in him, but the Father will also: "We will come to him and make our home with him" (14:23).

Arius used this text in the following way to help support his own error: the Lord says that he who receives him receives the Father; and so the relationship between the Father who sends and the Son is the same as that of the Son who sends and the disciples. But Christ who sends is greater than the disciples who are sent; thus, the Father is greater than the Son.

We should answer this, according to Augustine, by saying that there were two natures in Christ, a human and a divine nature. In the first part he is speaking with reference to his human nature, saying, he who receives any one whom I send receives me, as human, for I share with them in one human nature. In the second part he speaks in reference to his divinity: he who receives me, who am God, receives him who sent me, for I have the same divine nature as him.

Or, we could understand it to mean: he who receives one whom I send, receives me, for my authority is in him; and he who receives me receives the Father, whose authority is in me. In this way, these words show that Christ is the bridge between God and humankind, as in "There is one mediator between God and the men, the man Christ Jesus" (1 Tim 2:5).