Putting off the old and putting on the new is the principle by which the possibilities that are in Christ can become evident in our experience. “You lay aside the old self, which is being corrupted in accordance with the lusts of deceit, and that you be renewed in the spirit of your mind, and put on the new self, which in the likeness of God has been created in righteousness and holiness of truth.” (Eph. 4:22b-24) Paul tells us to constantly recognize the pull of the old life and reject these false, underlying assumptions that come from the old self–the old way of living. It is not merely deeds, you will notice, but outlooks and attitudes. This is what causes the problem, and this is what we must reject.
Put off means to divest yourself of something, to take it off. Paul is using the simplest of terms to illustrate what we must do in the realm of thought, of the attitudes of life. We must reject those basic assumptions that have caused our trouble—putting them off, rejecting them, divesting ourselves of them—just as you would put off your dirty clothes. We must do this because the corruption of life comes from these wrong attitudes.
The first step in experiencing what God intends for us is to recognize that. Put off the old. That is the first step. The other is to recognize the wonderful possibilities of the new life. In the NIV translation the phrase,
to be made new in the attitude of your minds, (v 23) you see the fundamental difference between a Christian and a non-Christian. It is true that non-Christians sometimes realize that things are wrong in their lives, and so they change them. But they change the outer form, but the problem remains basically the same: they are still dead in their sin.
But of all human beings, Christians alone have the possibility of doing something entirely different, living by an entirely different principle, because they have been renewed in the attitude of their minds. And that happens in the renewed life as the Spirit of God comes into the heart that believes in Jesus Christ. When we believe in Jesus Christ and receive Him as our Lord and Savior, we are renewed in the attitudes of our minds. The new self is in the likeness of God: it is the life of God; it is the image of Jesus Christ; it is His life lived in you. So put on that kind of life, because it is available to you. “I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave Himself for me.” (Gal. 2:20)