I can't speak for others, but I had similar questions in the past about being a Christian (Roman catholic). I thought a lot about it and also found examples from a priest that showed me what really matters and what not. This is how I view things:

There are actually two things at play here. One is the religion itself, and one is what the church tells me what to belief. The things about hell, having full faith and your example with the monk (I come back on that later) and people who lived before Christianity fall in the latter part. These are things that "governing bodies" like the church use to enforce their existence and power over people. As long as you except these things, there is not much of a problem (I visit the Church from time to time, but not every Sunday.) The thing that is IMHO most important and where God will "judge" you on when you die (again, I think God is not an evil entity, where you have to proof yourself to) is how good you lived. The bible is a book with nice stories that tells you what good and what bad is (some parts are outdated due to its age though). Use it as a guide through your live, but don't follow it to the word. If you look at it like that way, a Buddhist monk, a Muslim and a Christian follow all more or less the same rules, while they might not follow the same God.