Probably one of the best Manhwa out there. I highly suggest it to people who enjoy long battle stories similar to bleach, naruto, etc....
This mangwa is in no way religious. The "God" in the title merely reflects the power the Tower will give you if you reach the top, and many people can reach the top. It's all very very interesting.
At the moment it is #1 in my Manhwa/Manga list.
Introduction to the series from
http://towerofgod.wikia.com/wiki/Tow..._%28series%29:
Tower of God is a Manhwa series created by the Korean artist SIU. The story is centered around a boy named Baam who lives inside the massive, titular Tower and aims to find his childhood friend who wants to climb to the top. It is comprised of two seasons, Part I and Part II, the latter ongoing.
Part I
Twenty-Fifth Baam is a young man who had never experienced society and the presence of others except Rachel - the only girl he ever cared about and for. He desired nothing more than to continue living with her, but when Rachel wants a taste of the mythical Tower, she embarks on her journey, Baam desperately following in her tracks. Join Baam as he makes his journey through the Tower on his brave mission to find his best friend, makes friends, faces challenges and overcomes the tragedies he faces!
p.s. Thread may contain spoilers so I suggest you read the whole thing before posting here.