17 Now this I say and testify in the Lord, that you must no longer walk as the Gentiles do, in the futility of their minds. 18 They are darkened in their understanding, alienated from the life of God because of the ignorance that is in them, due to their hardness of heart. 19 They have become callous and have given themselves up to sensuality, greedy to practice every kind of impurity.

20-22 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, 23-24  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. Ephesians 4:17-24 (English Standard Version)

There are some interesting words in the Old Testament which say: “Don't eat the bread of a man who thinks only about himself. Don't desire his fine food. For as he thinks in his heart, so is he. He says, 'Eat and drink!' But his heart is not with you.” (Proverbs 23:6-7) The apostle Paul says something similar in vs 17 about the thinking of people who did not yet know Jesus Christ as Saviour and Lord. What does he say was the cause of the ‘futility’ of their minds. (vs 18)

The word futility means emptiness, or pointlessness. Even today many people think life has no meaning, and existence is so pointless. Paul says the underlying reason for such thinking is the darkness of people's understanding because of their ignorance of the true God, due to the hardness of their hearts. As in Proverbs, we see a link between mind and heart. What does Paul say this darkness resulted in? (vs 19)

He says they became even more callous (harder), and were willing to follow every impure lifestyle imaginable. We see this vividly today in the the way sex has been twisted beyond what God ever intended. Not just sex, things like meekness and mercy have also been scoffed at in the world. People have chosen impurity rather than purity. So what was Paul's call to those gentiles who had become Christians (vs 17), and how does he say the change in their lifestyle had come about? (vs 20-22)

They had 'learned Christ'! Psychiatrist's speak of 'learned behaviour' too, usually of a child in a home who becomes so much like one, or both, of their parents. Those gentiles who had heard about Christ, believed on Him, were then taught in Him, and began to be more like Him! The truth of who Jesus is and what He taught had brought light into their understanding so that they could see the rottenness of things they used to do, and they were casting away such deeds. Where had this life changing power taken place? (vs 22-23)

Paul says it was in 'the spirit of their minds'. They were once shaped by the futile thoughts of their dark minds, but now their minds had been renewed by Jesus Christ. The message of the gospel had brought them light. Not just any light – but the light of God Himself. They were no longer alienated from the true life that comes from God. They were learning His righteousness and holiness.

As I said earlier, there's a link between heart and mind. It's as if they interact upon each other. Paul put it well in a letter to Christians at Rome when he wrote: “I plead with you to give your bodies to God because of all he has done for you. Let them be a living and holy sacrifice - the kind He will find acceptable. This is truly the way to worship Him. Don’t copy the behaviour and customs of this world, but let God transform you into a new person by changing the way you think. Then you will learn to know God’s will for you, which is good and pleasing and perfect.” Romans 12:1-2 (Paraphrased translation.)

If what we think in our heart shapes what we become and what we are, let us make every effort to fill our hearts with Christ, and all that He taught. May His light flood our minds continually.