The key is BELEIF. Not acts of kindness, not how many alms were given to the poor, not haw many children you molest.
the key is not belief. even the devil believes in God, yet he's not saved. the key is faith, which is much different. faith encompasses even more than just believing something is true. faith produces good works. so if you know people who call themselves a christian, and are really bad, crappy people, then you ought to question his faith.