I do think it's fair to assume he was a Christian beforehand
Though I agree with the read of cultural Christians, it's interesting to point out that John's dog tags listed "non-religious." (Though, the Hidden Jew Theory would explain how Sam pulled Purim out of the air in "Red Sky At Morning" (even though he was off by several months).)
So mad that ABC is putting Lost up against SPN.
Hey, I finally have a good reason to give up Lost! (Let's not pay attention to the fact that I have a dual-tuner Tivo...)
The latest episode of Supernatural
Seriously, I read this as "the last episode," and my heart leapt to my throat.