SOGFPP,
I am glad to hear that you do not believe in modalism. This, like the orthodox trinity doctrine, is also a heresy. I can always learn more about church history. I do not deny that the heresy of the trinity began very early, I just do not believe that it began to be widely accepted until the third century. John warned against anti-christ which was even active in his day:
Little children, it is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time. 1 John 2:18
John described what these antichrist would teach:
Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son. 1 John 2:22
This is what the trinity heresy teaches. Jesus is not really a son, and the Father is not really his father.
Concerning your quotes, the quote from Justin Martyr does not suggest that he believed in the Trinity. I too believe that Christ holds a place next to His father; he sits on the right hand of his Father in heaven, but to say that therefor Martyr believed in the Trinity is a stretch.
If the reader would like to find out what really happened at the Council of Nicea, follow this link. It describes the effect of two heresies that arose in the early church. These heresies have become to be known as Arianism and orthodox Trinitarianism. These two camps fought for two centuries following the Council, but neither represented the majority view at that time. The majority view was summed up by Eusebius. A quote from his book follows.
http://www.presenttruth.info/books/Form_Trin/Form_Trin.htm
ÒFor as no one hath known the Father, but the Son, so no one on the other hand, can know the Son fully, but the Father alone, by whom He was begotten. For who but the Father hath thoroughly understood that Light which existed before the world was-that intellectual and substantial wisdom, and that living Word which in the beginning was with the Father, before all creation and any production visible or invisible, the first and only offspring of God, the prince and leader of the spiritual and immortal host of heaven, the angel of the mighty council, the agent to execute the FatherÕs secret will, the maker of all things with the Father, the second cause of the universe next to the Father, the true and only Son of the Father, and the Lord and God and King of all created things, who has received power, and dominion with divinity itself, and power and honour from the FatherÉ Where he introduces the Father and maker as the Ruler of all, commanding with His sovereign nod, but the divine word as next to Him, the very same that is proclaimed to us, as ministering to His FatherÕs commandsÉ The Son Himself, however, by no means indifferent to the worship of the Father, is appointed to teach the knowledge of the Father to allÉ Of Him, Moses obviously speaks as the second after the Father,É intrusted with the second rank of sovereignty and rule over all, Ôthe captain of the LordÕs host,ÉÕÓ (EusebiusÕ Ecclesiastical History, pages 15-17)
Eusebius expressed the view of most Christians at that time that Jesus was the only born Son of God, and not the only true God, not the only immortal God, not the one and only Potentate, not the supreme ruler of the universe. These early Christians (actually none of the camps) believed that the Holy Spirit was a third person as we think of one today, but instead was the Spirit of God, in much the same way that man has a spirit within him, the thing that knows a man's thought, and not a third seperate being.
P.S. Concerning the instruction for baptism, the apostles who heard what Jesus said, never followed the instruction as we believe it today. These holy men baptized in the name of the Lord Jesus Chirst, seemingly ignoring the rest of the instruction. They understood that Jesus was not promoting a new doctrine, the Trinity, Jesus was talking about the character that must be displayed in the one baptized and the effect that would be apparent in the changed life. In the name of Jesus, the old man is buried. In the name of the Father, the a new man is raised to newness of life, and when hands are layed on the new man, the Holy Spirit of God fills the new life, that he may live the life of Christ, who will not leave us alone but will come onto us.