Believer,
Why would a triune formula have been used in the early church when the candidate for baptism was declaring, in his baptism, his repentance and saving faith in the Lord Jesus Christ? Baptism had nothing to do with one's view of the nature of God, but with one's view of the person and work of Jesus Christ.
The NT call was to repentance and faith. This faith was to be directed toward Jesus Christ. As I've pointed out elsewhere, baptism was the time at which a confession "of Christ" was required. Christ said, "He that believeth on me, believeth not on me, but on him that sent me" (
John 12:44). It makes tremendous sense that any baptismal invocation would have been in the name of the Lord Jesus Christ. Just curious, do you think it was not?