Did you mean to say "developed in the fourth century?
Suffice to say I may well have been declared a Heretic with Arius. The question of "Trinity" in Scripture is an interesting one, based on Matthew 28:19 which did not exist in any MSS well into the 4th century and may well have been a "convenient" addition.
In any event, I accept Matthew 28:18 And Jesus came and said to them, All authority in heaven and on earth has been given to me."
That is enough for me.
You may or may not be interested in a rather lengthy discussion of the aunthenticity of Matthew 28:19. (I realize you may have no interest in opposing points of view. After all, your "mind is made up")
The following is a small sample:
ONE TEST is that of the CONTEXT
Examining the context, we find that in the AV the sense of the passage is hindered, but if we read as under, the whole context fits together and the tenor of the instruction is complete:
"All power is given unto ME ... go therefore... baptizing in MY name, teaching them... whatsoever I have commanded... I am with you..."
ANOTHER TEST is that of FREQUENCY
Is the phrase "in the name of the Father, Son and Holy Spirit" used elsewhere in Scripture? NOT ONCE!
Did Jesus use the phrase "in my name" on other occasions? YES! 17 times!
Matthew 18:5, 20; 24:5
Mark 9:37, 39, 41; 13:6; 16:17
Luke 9:48; 21:8
John 14:13, 14, 26; 15:16; 16:23, 24, 26.
ANOTHER TEST is that of ARGUMENT
Is any argument is Scripture based on the fact of the threefold name, or of baptism in the threefold name?
NONE Whatsoever!
Is any argument in Scripture based on the fact of baptism in the name of Jesus? Yes!
This is the argument in 1 Cor. 1:13. "Is Christ divided? Was Paul crucified for you? Were you baptized in the name of Paul?"
From this argument, if carefully analyzed, it will appear that believers ought to be baptized in the name of that One who was crucified for them. The Father, in His amazing love, gave us His beloved Son, who by the Spirit was raised to incorruptibility, but it is the Lord Jesus Himself who was crucified, and in HIS name, therefore, must believers be baptized in water.
"There is but one way for a believer of the things concerning the Kingdom of God, and the Name of Jesus the Christ, to put him on, or to be invested with his name, and that is, by immersion into his name. Baptism is for this specific purpose." Dr. Thomas, Revealed Mystery, Art. XLIV
"There is none other name under heaven" ―no other name or names― "given among men, whereby we must be saved." Acts 4:12
"As for its significance: baptism is linked inseparably with the death of Christ ―it is the means of the believer's identification with the Lord's death." God's Way, p190
Now the Father did not die, nor did the Spirit.
"Buried with him." (not the Father, Son, and Holy Ghost) ―Rom. 6:3-5.
"According to trine-immersion, it is not sufficient to be baptized into the Son. Thus Christ is displaced from his position as the connecting link-the door of entrance ―the 'new and living way.' And thus there are three names under heaven whereby we must be saved, in opposition to the apostolic declaration, 'that there is none other name (other than the name of Jesus Christ of Nazareth) under heaven given among men whereby we must be saved." Robert Roberts, The True Nature of Baptism, p. 13
This, of course, is the same argument as Paul's (see above), and although R.R. did not so intend, his argument is equally effective against the use of the triune name as against the practice of triune-immersion. Were ye baptized in the name of Paul, or the name of the Father, Son, and Holy Spirit, or in any other name that displaces Christ from his position as the 'connecting link,' as the ONLY name for salvation? That is the argument, and confirms the genuine text of Matthew 28:19 to contain the phrase "in my name."
ANOTHER TEST is that of ANALOGY
Is there anything in Scripture analogous to baptism in the Triune name? NO!
Is there anything analogous to baptism in the name of Jesus? YES!
The Father sent the Holy Spirit and baptized the waiting disciples with the Spirit in the name of Jesus. John 14:26. There is a reason for this. The Holy Spirit is the promise (Acts 2:33) which Christ received on ascending to the Father and only those who were in the corporate body of Christ, the Ecclesia, which is His Body-only those could receive the Gift, and only because they were in that one Body. The Lord Jesus Christ is the "connecting link" both for baptism in water and for baptism in spirit. John 3:5
ANOTHER TEST is that of CONSEQUENCE
In being baptized, do we put on the name of the Father, Son, and Holy Spirit? NO!
Do we put on the name of Jesus? YES!
"Believers of the Gospel Jesus preached are justified by faith through HIS name; that is, their Abrahamic faith and disposition are counted to them for repentance and the remission of sins, in the act of putting on the name of Jesus, the Christ." Dr. Thomas, Revealed Mystery, art. XLIII
Jesus said, "I am in my Father, and ye in me." John 14:20
Paul wrote, "Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death? 4Therefore we are buried with him by baptism into death." Romans 6:3-4, and again in Colossians 2:12, "Buried with him in baptism..." And in Galatians 3:26, "For as many of you as have been baptized into Christ have put on Christ."
ANOTHER TEST is that of PRACTICE
Did the Disciples afterwards baptize in the threefold name? NEVER!
Did they baptize in the name of Jesus? ALWAYS!
Acts 2:38, 8:16, 10:48, 19:5, 22:16, etc.
ANOTHER TEST is that of SIMILARITY OF ACTION
Baptism is a symbolic rite. The only other symbolic rite of the Ecclesia is that of breaking bread. The latter is the Communion of those who have experienced the former: and none else. This is the Lord's supper, not that of the trinity! (My body, My blood)
ANOTHER TEST is that of SIGNIFICANCE
One significance involved is that of the forgiveness of sins. Jo0hn did "preach the baptism of repentance for the remission of sins." Jesus had no sins to be remitted. Neither had he whereof to repent. When a man brought a lamb to the priest, he laid his hands upon the lamb, and the lamb was slain, and so the man received a remission of his sins. Without the laying on of hands the sin could not have been transferred tot he lamb. This is the significance of the baptism of Jesus by John. When we were baptized (as when John's disciples were baptized), our sins were loosed, remitted, washed away, and we arose sinless. The Lord entered the water of baptism to take upon himself those very sins. He entered sinless and emerged bearing the sins of the whole world!
How do we know?
It was revealed to John, who exclaimed. "Behold the Lamb of God which taketh away the sins of the world! John 1:29
It was Jesus alone (and not the Father, Son, and Holy Spirit) who was baptized, and became the Lamb of God to take away the sins of the world.
So that the significance here outlined requires the phrase in Matthew 28:19 to be "in my name."
ANOTHER TEST is that of PARALLEL ACCOUNTS
Now it happens that Matthew was not alone in recording the words of Jesus before his ascension. Let us compare the parallel accounts of Luke 24:46-47, who writes in the third person: And that repentance and remission of sins should be preached IN HIS NAME among all nations."
This passage therefore restores the correct text to Matthew 28:19-"in my name."
Futhermore, the last twelve verses of Mark record the last discourse of Jesus before his ascension. If these are to be regarded as the inspired writing of Mark himself, then we have yet another witness to the correct text, for Mark, after using similar words to Matthew- "go ye...all the world... preach.... Every creature...baptize..." Includes not the triune name but the phrase-"in my name."
ANOTHER TEST is that of COMPLEMENTARY CITATIONS
There is a striking resemblance between Matthew 28:19 and Romans 1:4-5. The former contains the Commision of Christ to his Apostles, while the latter is Paul's understanding and acceptance of his own Commission as an Apostle.
And then follows in Romans 1:5, not the triune name, but the phrase-"HIS NAME."
ANOTHER TEST is that of PRINCIPLE
It is written-"Whatsoever ye do in word or deed, do all in the name of the Lord Jesus." Colossians 3:17
Now here is a principle laid down, and the comprehensive word "whatsoever" certainly includes baptism, which is a rite involving both word and deed.
Now of the alternative readings of Matthew 28:19, the threefold name is clearly not in accordance with the above principle. The shorter phrase is. This item of Internal Evidence, therefore, proves which of the two variant readings is the spurious one.
That this is correct, is proved by other Scripture. It was Paul who enunciated the Principle. Did it, in his opinion, include baptism? Acts 19:3-5 supplies the answer. The baptism of John, like the Baptism of Jesus (then and now), was a baptism of repentance for the remission of sins. Mark 1:4, Acts 2:38-39. And John preached also the coming of the Messiah who should baptize with the Holy Spirit. The difference between the baptism of John and baptism after Pentecost is that the latter was in the name of JESUS.
NO OTHER DIFFERENCE IS SHOWN IN SCRIPTURE. Now it is written of the disciples at Ephesus that although they had been baptized unto John's baptism, they were later baptized again, in the presence of Paul, but "in the name of the Lord Jesus." Acts 19:3-5
This test provides a doubly-strong proof of the authenticity of the phrase "in my name" in Matthew 28:19.
God foreknew the record of the parting words of Jesus to his Disciples would be tampered with. He, in His wisdom, provided a remedy for those who have "eyes to see" in providing the principle enunciated by Paul in Colossians 3:17 and the record of Paul's application of that Principle in Acts 19:3-5.
A Collection of Evidence For and Against the Traditional Wording of the Baptismal Phrase in Matthew 28:19
THX THX.
Did you mean to say "developed in the fourth century?
Negative; the Church worked out the Trinitarian formula over at least two centuries. Suffice to say I may well have been declared a Heretic with Arius. The question of "Trinity" in Scripture is an interesting one, based on Matthew 28:19 which did not exist in any MSS well into the 4th century and may well have been a "convenient" addition.
It is possible, sure.
In any event, I accept Matthew 28:18 And Jesus came and said to them, All authority in heaven and on earth has been given to me."
That is enough for me.
By those standards, the Latter Day Saints or the Jehovah's Witnessess might be fellow believers with you. Or even the Oneness Pentecostals, most of them anyway.
Is there anything in Scripture analogous to baptism in the Triune name? NO!
Aside from the baptismal formulation in Matthew, which you so very well expound on, there is nothing explicit. The very tag of Unitarianism means one God and no 'personages', if I understand the tag correctly. Would you consider that correct?
I had not thought that you considered the Pauline epistles so highly (even more if you consider Acts, written by Luke, first a Petrine apostle, then a Pauline one) and take as much from Paul as proofs of your faith. Very interesting.