I had read Church articles of faith from a book by Baba Shnouda II and I do not want to judge others' faith, but I think that Church Creed is established by the Paulus and also by Church Fathers later in the 50th of CE during the Council of Jerusalem and it continues on to the Council of Chalcedon.
The book talked about the nature of the person Jesus whether he is divine or human or both of the nature being regarded as a unity and after that they never talk about them in separation anymore like the diophysites. There isn't any mention yet about Trinity because Spiritu Sanctu (Hly Ghost) wasn't yet being included in the Godhead in the early time but Jesus divinity had been debated by those Early Church Fathers.
www.copticchurch.net/topics/theology/nature_of_christ.pdf
I had read something about Tertullianus too in other books. At the beginning I read those books including about Christians' Creed, it's quite a dizzy experience and time for me because I've personally founded that Christians Creed is quite complicated with Church Fathers' words play and I have to think back in Arabic.