If you have two shirts in your closet, one belongs to you and the other to the man with no shirt.
Ambrose... these three witnesses are one, as John said: 'The water, the blood, and the Spirit' (I Jn. 5:8). One in the mystery, not in nature. The water, then, is a witness of burial, the blood is a witness of death, the Spirit is a witness of life. If, then, there be any grace in the water, it is not from the nature of water, but from the presence of the Holy Spirit.
AmbroseThe Lord was Baptized, not to be cleansed Himself, but to cleanse the waters, so that those waters, cleansed by the flesh of Christ which knew no sin, might have the power of Baptism.
Ambrose