Bible Dictionary
OLD MAN
The old man is Paul’s term for the unrenewed human nature corrupted by sin. Through union with Christ, believers are called to put off this former manner of life and live as new people in righteousness.
Biblical Usage
Paul contrasts the old man with the new man. The old man is associated with sinful desires and the works of the flesh, while the new man is created in righteousness and true holiness and belongs to the Spirit.