Because Christians condemn the way a lot of people live (premarital sex, homosexuality, etc) I argue that they should practice forgiving those people (who they perceive as sinners) and tolerating their differences without enforcing the rules of their beliefs on nonbelievers. Also, because the root of Christianity is in the belief that people are sinners and God forgives sin, so they’re supposed to ask for forgiveness for their sins by accepting God into their heart.