Old Man

(palaios, "old," "ancient"): A term thrice used by Paul (Ro 6:6; Eph 4:22; Col 3:9) to signify the unrenewed man, the natural man in the corruption of sin, i.e. sinful human nature before conversion and regeneration. It is theologically synonymous with "flesh" (Ro 8:3-9), which stands, not for bodily organism, but, for the whole nature of man (body and soul) turned away from God and devoted to self and earthly things.

⇒See the definition of old in the KJV Dictionary

The old man is "in the flesh"; the new man "in the Spirit." In the former "the works of the flesh" (Ga 5:19-21) are manifest; in the latter "the fruit of the Spirit" (Ga 5:22-23). One is "corrupt according to the deceitful lusts"; the other "created in righteousness and true holiness" (Eph 4:22-24 the King James Version).