John 20:28

And immediately they believed that He was Christ. Wherefore Thomas also says to Him, "My Lord, and my God." These things did He do, and showed Himself risen, and they believed.

No king, with Him, finds greater favour, no barbarian lesser joy; no dignities or pedigrees enjoy distinctions of merit; to all He is equal, to all King, to all Judge, to all "God and Lord." Nor would you hesitate to believe what we asseverate, since you see it taking place.

Let them therefore confess, even they who previously denied that the crucified was God, that they have erred. For the divine Scriptures bid them, and especially Thomas, who, after seeing upon him the print of the nails, cried out, “My Lord and my God.”

You have read that the Father is both Lord and God: “O Lord my God, I will call on you, hear me.” You find the Son to be both Lord and God, as you have read in the Gospel, that, when Thomas had touched the side of Christ, he said, “My Lord and my God.” So just as the Father is God and the Son Lord, so too the Son is God and the Father Lord. The holy designation changes from one to the other. The divine nature does not change, but the dignity remains unchangeable. For they are not [as it were] contributions gathered from bounty but free-will gifts of natural love. For unity has its special property, and the special properties are bound together in unity.

And not in this way only did Jesus rebuke him, but also by what follows; for when he, being fully satisfied, breathed again, and cried aloud, "My Lord, and my God," He saith, "Because thou hast seen Me, thou hast believed; blessed are they who have not seen, and yet have believed."

And [Thomas] touched him carefully, and when he discovered the truth, confessed his fault by saying, “My Lord and my God!” What does this mean? While Thomas did not believe before that the Savior had resurrected from the dead, now he calls him Lord and God? This is not likely. Thomas, the doubtful disciple, does not call Lord and God the one whom he touched—in fact, the knowledge of the resurrection did not teach him that the resurrected one was God. Rather, he praised God for the accomplished miracle, being astonished for the miracles that he saw.

You have heard that those who do not see and believe are more praised by the Lord than those who see and believe, and even those who have been able to touch. For the apostle Thomas, when the Lord had shown himself to his disciples, was absent; and when he heard from them that Christ had risen, he said: Unless I put my hand into his side, I will not believe. What if, then, the Lord had risen without scars? Indeed, could he not have resurrected his flesh, so that no traces of wounds would remain in it? He could have done this; but unless he had retained the scars on his body, he would not have healed the wounds in our heart. He was touched, and he was recognized. It was not enough for him to see with his eyes; he wanted to believe with his fingers. Come, he says, put your fingers here; I did not take everything away, I kept something for you to believe in; and see my side, and do not be unbelieving, but faithful. But when he revealed to him what had remained doubtful, he exclaimed: My Lord and my God. He was touching the flesh, and he was calling out to the divinity. What did he touch? The body of Christ. Was the body of Christ the divinity of Christ? The divinity of Christ was the Word; the humanity of Christ was soul and flesh. He could not touch the soul itself, but he could understand it, because the body which had been dead was moving alive. But that Word is neither changed nor touched, neither diminished nor increased; because in the beginning was the Word, and the Word was with God, and the Word was God. This is what Thomas cried out; he was touching the flesh, he was invoking the Word, because the Word was made flesh, and dwelt among us.

(Tr. cxxi) Thomas saw and touched the man, and confessed the God whom he neither saw nor touched. By means of the one he believed the other undoubtingly: Thomas answered and said unto Him, My Lord and my God.

"But Thomas, one of the twelve, who is called Didymus, was not with them when Jesus came. The other disciples therefore said unto him, We have seen the Lord. But he said unto them, Except I shall see in His hands the print of the nails, and put my finger into the place of the nails, and put my hand into His side, I will not believe. And after eight days, again His disciples were within, and Thomas with them. Then came Jesus, the doors being shut, and stood in the midst, and said, Peace be unto you. Then saith He to Thomas, Reach hither thy finger, and behold my hands; and reach hither thy hand, and put it into my side: and be not faithless, but believing. Thomas answered and said unto Him, My Lord and my God." He saw and touched the man, and acknowledged the God whom he neither saw nor touched; but by the means of what he saw and touched, he now put far away from him every doubt, and believed the other. "Jesus saith unto him, Because thou hast seen me, thou hast believed." He saith not, Thou hast touched me, but, "Thou hast seen me," because sight is a kind of general sense. For sight is also habitually named in connection with the other four senses: as when we say, Listen, and see how well it sounds; smell it, and see how well it smells; taste it, and see how well it savors; touch it, and see how hot it is. Everywhere has the word, See, made itself heard, although sight, properly speaking, is allowed to belong only to the eyes. Hence here also the Lord Himself says, "Reach hither thy finger, and behold my hands:" and what else does He mean but, Touch and see? And yet he had no eyes in his finger. Whether therefore it was by looking, or also by touching, "Because thou hast seen me," He says, "thou hast believed." Although it may be affirmed that the disciple dared not so to touch, when He offered Himself for the purpose; for it is not written, And Thomas touched Him. But whether it was by gazing only, or also by touching that he saw and believed, what follows rather proclaims and commends the faith of the Gentiles: "Blessed are they that have not seen, and yet have believed." He made use of words in the past tense, as One who, in His predestinating purpose, knew what was future, as if it had already taken place.

Thomas, when he touched the flesh, believed that he had touched God, saying, “My Lord and my God.” For they all confessed but one Christ, so as not to make him two. Do you therefore believe him? And do you believe in such a way that Jesus Christ the Lord of all, both Only Begotten and firstborn, is both creator of all things and preserver of humanity and that the same person is first the framer of the whole world and afterward redeemer of humankind?

He that had shortly before been slack in the duty of faith was now eager to profess it. and in a short time his fault was wholly cured. For after an interval of only eight days the hindrances to his faith were removed by Christ, Who showed unto him the print of the nails and His wounded Side. But, perhaps, someone will ask the question: "Tell me why did the minds of the holy disciples carry out so rigid an inquiry, and so careful a scrutiny? For would not the sight of the Lord's Body, the features of His Face, and the measure of His Stature, have sufficed to prove that He had indeed risen from the dead, and to secure His recognition?" What do we reply? The inspired disciples were not free from doubt, although they had seen the Lord. For. they thought that He was not in very truth the same as He Who of old had lived and dwelt among them, and had hung upon the Cross, but rather that He was a Spirit, cunningly fashioned like unto our Saviour's Image, and simulating the features of the form which they knew. For they fell into this delusion not without some apparent excuse, as He miraculously entered when the doors were closed; in spite of the fact that a body of coarse earthy mould requires a hole through which it can pass, and necessitates the aperture of the door to correspond in width with the size of the body. For this cause our Lord Jesus Christ, greatly to our profit, laid bare His Side to Thomas, and exposed the wounds on His Person, through his agency giving adequate proof to all. For though of Thomas alone is recorded the saying: Except I shall put my hands and see the prints of the nails, and put my hand into His Side, I will not believe, yet was the charge of lack of faith common to them all; and we shall find that the minds of the other disciples were not free from perplexity, though they said unto the holy Thomas: We have seen the Lord. And that what we say does not err from the truth we may easily perceive by what the Divine Luke tells us: As they spake these things, He stood in the midst of them, that is, of course, Christ, and saith unto them, Peace be unto you. But they were terrified and affrighted, and supposed that they beheld a spirit. And He said unto them, Why are ye troubled? and wherefore do reasonings arise in your hearts? See My Hands and My Feet, that it is I Myself: handle Me, and see; for a spirit hath not flesh and bones, as ye behold Me having. And when He had said this, He showed them His Hands and His Feet. And while they still disbelieved for joy, and wondered, He said unto them, Have ye here anything to eat? And they gave Him a piece of a broiled fish, and of an honeycomb. And He took it, and did eat before them. You see how the thought of unbelief is found lurking, not in the blessed Thomas alone, but that the minds of the other disciples were afflicted with a kindred disease. For, lo and behold! seeing that their faith wavered even after the sight of the wounds upon the Cross, He thought it right to convince them by another act, in nowise suited to a spirit, but specially appropriate to earthly bodies and the nature of flesh. For He ate the fish that was brought unto Him, or the portion of one. For when no mark at all of corruption any longer remained after the Resurrection of His holy Flesh, because He lived again to incorruption, and when it was incredible that His Body stood in need of food as heretofore, He yet showed unto them the print of the nails, and did not refuse to partake of food, in order that He might establish the great mystery of the Resurrection, and cause faith in it to spring up in the souls of us all. He does acts wholly alien to the nature of spirits. For how, and in what way, could the prints of nails, and the traces of wounds, and participation in bodily food, be found to exist in a naked spirit unconnected with flesh, to which all these things are suitable by the law of its being and the conditions under which it exists? In order, then, that none might think that Christ rose again a mere spirit, or an impalpable body, shadowy and ethereal, to which some give the name of spiritual, but that the selfsame body that was sown in corruption, as Paul saith, might be believed to have risen again, He openly did acts suitable to a palpable human form. What we said at first, however, namely, that the blessed disciple did not so much lack faith owing to infirmity of judgment, but rather was affected in this way by excess of joy, will not be wide of the mark. For we have heard the saying of the blessed Luke concerning all the others: And while they disbelieved for joy and wondered. It was wonder, therefore, that made the disciples slow to be convinced. But as henceforward there was no excuse for unbelief, as they saw with their own eyes, the blessed Thomas accordingly unflinchingly confessed his faith in Him, saying: My Lord and my God. For we must all confess that it follows of a surety that He That is Lord by Nature and Ruler over all is also God, just as also universal dominion and the glory of sovereignty is clearly seen to appertain to the living God.

Observe, too, that when he says My Lord and my God, he uses the article to show that there was One Lord and One God. For he does not say without the qualification of the article, My Lord and my God, to prevent any one from imagining that he called Him Lord or God as he might have done one of ourselves or of the holy angels. For there are gods many and lords many, in this sense, in heaven and on earth, as the wise Paul has taught us; but rather he recognises Him as, in a special sense, the One Lord and God, as begotten of the Father, Who is by Nature Lord and God, when he says, My Lord and my God; and, what is a still greater indication of the truth, the Saviour heard His disciple saying this, and saw that he rested in the firm conviction that He was, in fact, the Lord and God, and thought it not right to rebuke him. Christ, then, approved his faith, and with justice. And you may easily see that what I say is true. For to him that was possessed of this faith He says, at the end of the Gospel, as unto the rest: Go ye and make disciples of all the nations. And if He bids him who was thus minded teach all nations, and appointed him to instruct the world in His mysteries, He wishes us to have a like faith. For He is, in fact, Lord and God by Nature, even when Incarnate Man. For observe that the disciple, when he had touched His Hands, and Feet, and Side, made unto Him this confession of faith, not severing Emmanuel into a duality of Sons, but recognising Him as one and the same in the Flesh, for Jesus Christ is One Lord, according to the Scripture.

But he touched, and exclaimed: My Lord, and my God. Jesus says to him: Because you have seen me, Thomas, you have believed. Since the apostle Paul says: Now faith is the substance of things hoped for, the evidence of things not appearing, it is certainly clear that faith is the evidence of those things which cannot appear. For those things which appear no longer have faith, but recognition. Therefore when Thomas saw, when he touched, why is it said to him: Because you have seen me, you have believed? But he saw one thing, he believed another. For divinity could not be seen by a mortal man. Therefore he saw the man, and confessed God, saying: My Lord, and my God. Therefore by seeing he believed, who considering the true man, exclaimed that this was God, whom he could not see.

See how he who at first did not believe, from touching the side became an excellent theologian. For he proclaimed two natures and one person in the one Christ. By saying "Lord," he confessed the human nature, for "Lord" is used of men as well, for example: "Sir, if you have carried Him away" (John 20:15). And by saying "my God," he confessed the divine essence, and thus confessed One and the Same as both Lord and God.

He who had been before unbelieving, after touching the body showed himself the best divine; for he asserted the twofold nature and one Person of Christ; by saying, My Lord, the human nature, by saying, My God, the divine, and by joining them both, confessed that one and the same Person was Lord and God.
Jesus saith unto him, Because thou hast seen Me, thou hast believed.

Here He means the disciples who had believed without seeing the print of the nails, and His side.

2562 The Evangelist now mentions Thomas' profession. It seems that Thomas quickly became a good theologian by professing a true faith. He professed the humanity of Christ when he said, My Lord, for he had called Christ this before the passion: "You call me Teacher and Lord" (Jn 13:13). And he professed the divinity of Christ when he said, and my God. Before this, the only one who had called Christ God was Peter: "You are the Christ, the Son of the living God" (Mt 16:16); "This is the true God and eternal life" (1 Jn 5:20).