Christians who have been awakened by the voice of Jesus, have been given a new eternal life within and who are now in the school of Christ waiting and eager to be taught how to live, no longer like the Gentiles in the futility of their minds (v. 17) but like new creatures whose lives are full of meaning and hope and joy.

After you hear the voice of Christ and are made alive and brought to faith in Him and let Him teach you how to live, the first thing He says to you is: “change your clothes.” Take off the old person and put on the new person. “But that is not the way you learned Christ!—assuming that you have heard about Him and were taught in Him, as the truth is in Jesus, to put off your old self, which belongs to your former manner of life and is corrupt through deceitful desires, and to be renewed in the spirit of your minds, and to put on the new self, created after the likeness of God in true righteousness and holiness.” (Eph. 4:20-24)

What is the old person and what is the new person? The next verse gives a helpful clue. “Therefore, having put away falsehood, let each one of you speak the truth with his neighbor, for we are members one of another.” (v 25)  The Lord tells us to let go of our former selves with our bad practices that belong to the old way of life—like lying.

Another good clue to the meaning of “the old person” is found here: “But now put them all away: anger, wrath, malice, slander, and foul talk from your mouth. Do not lie to one another, seeing that you have put off the old person with its practices.” (Col. 3:8-9) Putting off the old person is more than putting off old practices, because we put it off WITH its practices. The passage mentions things that lie beneath and behind practices—like anger and wrath. So the old person is the old bundle of attitudes and emotions and practices that I used to be. That’s who I was before I was called out of darkness by the voice of Jesus and began to be taught in His school.

The new person is the new bundle of attitudes and emotions and practices that Jesus has called us to become in His teaching. “Put on then, as God’s chosen ones, holy and loved, compassion, kindness, lowliness, meekness, and patience.” (Col. 3:12) So We must take off the old person and put on the new person. It is absolutely imperative that we get our moral clothes changed. If we don’t, we will not graduate. We will not make it to heaven.

Unlike the world, the Lord sees into our hearts and knows our true selves. If we make a “show” of following Him externally, but we don’t seek Him and His will with all our hearts, we gain nothing. Jesus cautioned us, “Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but the one who does the will of my Father who is in heaven.” (Matt. 7:21)

When Paul says, put off the old person and put on the new person, he is not talking about an optional elective that some true Christians enroll in and others don’t. This is the core curriculum in the teaching of Christ. It is a requirement for graduation. “Strive for peace with everyone, and for the holiness without which no one will see the Lord.” (Hebrews 12:14) Therefore, “put on the new self, created after the likeness of God in true righteousness and holiness”. (Eph. 4:24) 

The great news is that we aren’t required to make our own moral clothing: God creates the new person that we must put on. I am given the assignment to become holy; but then I am told that God creates my holiness. In the school of grace God creates the new person—and that includes all the new attitudes and emotions and practices that we are supposed to put on. “For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them.” (Eph. 2:10)