Romans 6:3

Verse 3. and so forth We … are baptized in his death. Greek, unto his death. The apostle here alludes to the manner of administering the sacrament of baptism, which was then done by immersion or by plunging the person baptized under the water, in which he finds a resemblance of Christ’s death and burial under ground, and of his resurrection to an immortal life. So must we after baptism rise to lead a quite different life: having been also, when we were baptized and made Christians, planted as branches ingrafted in Christ, let us endeavour to bring forth the fruits of a virtuous life. Witham.—Old man … body of sin. Our corrupt state, subject to sin and concupiscence, coming to us from Adam, is called our old man, as our state, reformed in and by Christ, is called the new man. And the vices and sins which then ruled in us, are named the body of sin. Challoner.—The old and sinful man we must look upon as crucified with him, and the body of sin, or our sinful body, destroyed. We must look upon ourselves as dead to sin, and that we must sin no more, as Christ being once risen, dies no more. Witham.