Matthew 18:16-18
16 But if he will not listen, take one or two others along, so that ‘every matter may be established by the testimony of two or three witnesses.’
17 If he refuses to listen to them, tell it to the church; and if he refuses to listen even to the church, treat him as you would a pagan or a tax collector.
18 “I tell you the truth, whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.