Explainer / Messiah

Matthew 28:19

Go therefore, and make disciples of all the nations, baptizing them into the name of the Father and of the Son and of the Holy Spirit:

πορευθέντες οὖν μαθητεύσατε πάντα τὰ ἔθνη, βαπτίζοντες αὐτοὺς εἰς τὸ ὄνομα τοῦ πατρὸς καὶ τοῦ υἱοῦ καὶ τοῦ ἁγίου πνεύματος.

Greek

What we did

We kept the ASV's wording, in modern English, including the threefold name.

Why

The manuscripts
Every surviving Greek manuscript of Matthew 28 has the threefold name, and so do all early versions that contain the passage.
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This version prints it.
Eusebius
Eusebius of Caesarea (early 4th century) quotes the verse several times in a shorter form, "make disciples of all nations in my name," and later quotes the longer form.
"Into the name."
εἰς τὸ ὄνομα is "into the name," as the ASV has it.
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ὄνομα is singular: "the name," followed by three genitives, "of the Father and of the Son and of the Holy Spirit."