Religious beliefs do not make people good and incapable of being corrupted by material wealth. It is the goodness of one's heart. It is one's morals and principles, one's character, that makes someone good and incapable of being corrupted by material wealth.
Religious or not, people will still lie, cheat, slander and kill. Religion has no say in what one does or does not do. There is no religion that forbids wrongdoing, and even if there was such a religion, people will still engage in wrongdoing given the right reasons or circumstances, or if forced to.
After all, every religion has its own failsafe, it's own laundry chamber where one's sins, intentionally committed or otherwise, can be washed away like soiled linen can be washed and made like new.
Catholics have a confessional booth, Muslims have the black stone.
Isn't God great in this respect?