Ephesians 4:20-24 (KJV)
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.
When you read the verses 17 to 19 it provides a general description of and the reason of sinful behaviour. (“Ephesians 4:17-19 (KJV) 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.”)

In verses 20 to 24 we see that what we should do is not just stoping sinful behaviour but replacing it with godly behaviour. If we don’t replace it (by putting on) then we easily pick up and put back on the sinful behaviour. After these verses are listed some examples of putting off and putting on. Let’s have a look at them.

Ephesians 4:25-32 (KJV) 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. 29 Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace unto the hearers. 30 And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption. 31 Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice: 32 And be ye kind one to another, tenderhearted, forgiving one another, even as God for Christ’s sake hath forgiven you.
In summary what we are to put on is all a fruit (a result) of walking in love.
Then chapter five continues with the theme and shows us more on how we walk in the love of GOD. We might look at this another time.
For now let us examine ourselves and see if there is anything we need to ask the LORD to forgive us from, to show us what we are to replace it with, and help us to repent by putting off and then put on the behaviour He wants us to.