Albert Barnes on Matthew 18:18

Whatsoever ye shall bind, Mt 16:19. These words were spoken to the apostles. He had used the same words to Peter, Mt 16:19. He used them here to signify that they all had the same power; that in ordering the affairs of the church he did not intend to give Peter any supremacy, or any exclusive right to regulate it. The meaning of this verse is, whatever you shall do in the discipline of the church shall be approved by God, or bound in heaven. This promise, therefore, cannot be understood as extending to all Christians or ministers; for all others but the apostles may err.

(p) "whatsoever ye shall bind" Mt 16:19, Jn 20:23, Acts 15:23-31 2Cor 2:10