Matthew 5:22-24

22But I can guarantee that whoever is angry with another believer  will answer for it in court. Whoever calls another believer an insulting name will answer for it in the highest court. Whoever calls another believer a fool will answer for it in hellfire.

23“So if you are offering your gift at the altar and remember there that another believer has something against you,

24leave your gift at the altar. First go away and make peace with that person. Then come back and offer your gift.