That's begging the question.
Which version of each creed is definitive?
With the exception of the Filioque, I'm not aware of any significant differences in versions or translations.
The Nicene Creed dates from the fourth century; the Athanasian Creed is even later. What about those who lived before these creeds were formulated? Would they be considered Christians in your view?
Interesting question, but a red herring in the present discussion.
I am told that the Eastern Orthodox do not formally recognize either the Apostles' Creed or the Athanasian Creed. (Someone please correct me if I am wrong.) Are they Christians?
Related to the issue of the Filioque, IMO. The Nicene Creed is the official creed of the EO, but Im not aware that the EO would deny anything in either of those other creeds (with the exception of the Filioque).
Well, the Filioque is a rather big exception, considering the role it played in the schism between the Eastern and Western Churches.
Interesting question, but a red herring in the present discussion.
Not at all. Any definition of Christian which excludes the early Apostles and saints strikes me as absurd.
The Nicene Creed is the official creed of the EO, but Im not aware that the EO would deny anything in either of those other creeds (with the exception of the Filioque).
What about those Protestants who claim to be "non-creedal"? Are they Christians according to your definition?
I think a better starting point in defining who is a Christian would be those that follow Jesus, seeking to live a Christ like life, knowing Jesus is the son of God and through him alone salvation is found.