I am one that bear witness of myself, and the Father that sent me beareth witness of me.
Ver. 18. I am one that bear witness, &c.] Christ is alius from his Father, not aliud; another person, not another thing. As in the person of Christ there is aliud et aliud another and another (against Eutyches), not alius et alius different and different (against Nestorius). In this text, the Divinity of Christ is plainly distinguished from his humanity; how else should he and the Father be two witnesses to himself?