Matthew 18:17-18

17If he pays no attention to them [refusing to listen and obey], tell it to the church; and if he refuses to listen even to the church, let him be to you as a Gentile (unbeliever) and a tax collector.

18I assure you and most solemnly say to you, whatever you bind [forbid, declare to be improper and unlawful] on earth shall have [already] been bound in heaven, and whatever you loose [permit, declare lawful] on earth shall have [already] been loosed in heaven.