Even if we cannot find or access early manuscripts before the fourth century to see if they contain Matthew 28.19, we can still consult the many Christian authors who lived in the second and third centuries to see how they CITED IT. Below is a list of a few quotations.
Didache (a.d. 60-150) chapter 7.1-4
“Now about baptism: this is how to baptize. Give public instruction on all these points, and then baptize in running water, in the name of the Father and of the Son and of the Holy Spirit. If you do not have running water, baptize in some other. If you cannot in cold, then in warm. If you have neither, then pour water on the head three times in the name of the Father, Son, and Holy Spirit. Before baptism, moreover, the one who baptizes and the one being baptized must fast, and any others who can. And you must tell the one being baptized to fast for one or two days beforehand.”
First Apology by Justin Martyr (a.d. 155) chapter 61
“…Then they are brought by us where there is water, and are born again, for they then receive washing in water in the name of God the Father and Master of all, and of our Savior Jesus Christ, and of the Holy Spirit. For Christ also said, ‘Except you are born again, you will not enter into the Kingdom of Heaven.’…”
Against Heresies by Irenaeus (a.d. 180) book 3 chapter 17.1
“…And again, giving to the disciples the power of regeneration into God, he said to them, ‘ Go and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Spirit.’…”
On Baptism by Tertullian (a.d. 198) chapter 13
“For the law of baptizing has been imposed, and the formula prescribed: ‘Go,’ He saith, ‘teach the nations, baptizing them into the name of the Father, and of the Son, and of the Holy Spirit.’ The comparison with this law of that definition, ‘Unless a man have been reborn of water and Spirit, he shall not enter into the kingdom of the heavens,’ has tied faith to the necessity of baptism.”
The Apostolic Tradition by Hippolytus (a.d. 200-235) chapter 21.12-18
“And when he who is baptized goes down into the water, he who baptizes him, putting his hand on him, shall say thus: Do you believe in God, the Father Almighty? And he who is being baptized shall say: I believe. Then holding his hand placed on his head, he shall baptize him once. And then he shall say: Do you believe in Christ Jesus, the Son of God, who was born of the Holy Spirit of the Virgin Mary, and was crucified under Pontius Pilate, and was dead and buried, and rose again on the third day, alive from the dead, ascended into heaven, and sat at the right hand of the Father, and will come to judge the living and the dead? And when he says: I believe, he is baptized again. And again he shall say: Do you believe in holy spirit , and the holy church, and the resurrection of the flesh? He who is being baptized shall say accordingly: I believe, and so he is baptized a third time.”
Epistle to Magnus by Cyprian (a.d. 250) chapter 7
“…But if any one objects, by way of saying that Novatian holds the same law which the universal church holds, baptizes with the same symbol with which we baptize, knows the same God and Father, the same Christ the Son, the same Holy Spirit, and that for this reason he may claim the power of baptizing, namely, that he seems not to differ from us in the baptismal interrogatory; let any one that thinks that this may be objected, know first of all, that there is not one law of the creed…”
The traditional reading of Matthew 28.19 was alive and well before a.d. 325 and people knew about it. Furthermore, I have not found any controversy over the authenticity of this text anywhere. This is mounting up to be a really solid case: not only do ALL extant Greek manuscripts with Matthew 28.19 in them contain the traditional reading, but all of the church fathers in the second and third century that quote or allude to it use the traditional version. Suddenly the case from Eusebius’ quotations does not seem so impressive. Even so, let’s consider Eusebius’ statements to better understand what is happening…