Matthew 18:15

Mat 18:15  Moreover if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother.

Mat 18:16  But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established.

Mat 18:17  And if he shall neglect to hear them, tell it unto the church: but if he neglect to hear the church, let him be unto thee as an heathen man and a publican.