Using the illustration of clothing, Paul reminds us that the truth that is in Jesus is defined by our having put off the old man and put on the new man, in the same manner that one would exchange an old garment for a new one. (Read Rom 6:6 Gal 2:20, and Col 3:9). The old man is not renewed; rather he is dead and in the process of decaying, as he has grown corrupt through the deceitful lusts that compelled his activities. Put off is in the aorist tense and infinitive mood; rather than a command, it states a definitive, decisive and permanent act that has already been accomplished. Greek scholar Kenneth Wuest expands the translation of Ephesians 4:21 as follows: that you have put off once for all with reference to your former manner of life the old self who is being corrupted according to the passionate desires of deceit.
Verse 24 adds the positive counterpart of the negative of verse 22 – that you put on the new man. While the old man was corrupt and degenerating to the point of ruin, the new man has been freshly created after the likeness of God in righteousness and holiness. The descriptions of the old man and the new man are so dissimilar that their total incompatibility cannot be emphasized more clearly. Just like put off, the verb put on is also an aorist infinitive– Wuest translates verse 24 as follows: and that you have put on once for all the new self who after God was created in righteousness and holiness of truth.