“17 This I say therefore, and testify in the Lord, that ye henceforth walk not as other Gentiles walk, in the vanity of their mind, 18 Having the understanding darkened, being alienated from the life of God through the ignorance that is in them, because of the blindness of their heart: 19 Who being past feeling have given themselves over unto lasciviousness, to work all uncleanness with greediness. 20 But ye have not so learned Christ; 21 If so be that ye have heard him, and have been taught by him, as the truth is in Jesus: 22 That ye put off concerning the former conversation the old man, which is corrupt according to the deceitful lusts; 23 And be renewed in the spirit of your mind; 24 And that ye put on the new man, which after God is created in righteousness and true holiness. 25 Wherefore putting away lying, speak every man truth with his neighbour: for we are members one of another. 26 Be ye angry, and sin not: let not the sun go down upon your wrath: 27 Neither give place to the devil. 28 Let him that stole steal no more: but rather let him labour, working with his hands the thing which is good, that he may have to give to him that needeth.”
There is a lesson plan written in the verses at hand in Ephesians 4:17-28 (see above): a lesson about who you are and a lesson about how unholy that person is or was. Vanity…before we put on the mind of Christ, everything we did was in vain. It was done out of depravity. It was an empty promise or word spoken because the desired result was probably selfish or a lie (v 17). This is the skin we walk in if we do not allow Christ to live within us; it is a way of living that keeps us alienated or separated from God because what we do, He does not condone for we walk in a way that is not becoming of Him (v 18).
We live lives that do not please God. Our lasciviousness or filthiness (our thoughts and actions which are ungodly) are done for selfish reasons (v 19) because we have yet to get to know Christ (v 20). For if we did know Christ: if we had heard his voice, studied His ways, we would see He speaks and walks in truth (v 21). By seeing His example we would no longer desire to resemble our past SELF, for he/she was corrupt in thought and desire of the flesh (v 22).
Instead, be a new person by the renewing of your mind and spirit (v 23). Wear a new skin, the one God intended for you when He created you and become holy and righteous (v 24). This means you shall no longer resemble the person who was deceitful, instead being truthful with everyone; you are now part of the body of Christ (v 25).
It is okay to have righteous anger but do not carry it into the next day; resolve it justly immediately as not to carry wrath in your heart (v 26). Never allow the devil to find a foothold in your life, it’s dangerous (v 27)! Make a person who was once deceitful work for all he has: this keeps his/her mind occupied. For all good things to come require a work in the self, and in life, in order to serve others unselfishly in the end (v 28).