Mt 5:20-26
‘For I tell you, if your uprightness does not surpass that of the scribes and Pharisees, you will never get into the kingdom of Heaven. ‘You have heard how it was said to our ancestors, You shall not kill; and if anyone does kill he must answer for it before the court. But I say this to you, anyone who is angry with a brother will answer for it before the court; anyone who calls a brother “Fool” will answer for it before the Sanhedrin; and anyone who calls him “Traitor” will answer for it in hell fire. So then, if you are bringing your offering to the altar and there remember that your brother has something against you, leave your offering there before the altar, go and be reconciled with your brother first, and then come back and present your offering.