Matthew 18:16 in the King James Version
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.
Context
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.
16 But 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.
17 If 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.