Matthew 18:15-17

¹⁵"If your brother sins against you, go, show him his fault between you and him alone. If he listens to you, you have gained back your brother. ¹⁶But if he doesn`t listen, take one or two more with you, that at the mouth of two or three witnesses every word may be established. ¹⁷If he refuses to listen to them, tell it to the assembly. If he refuses to hear the assembly also, let him be to you as a Gentile or a tax collector.