Colossians 3, verses 5-9 I’ve titled this ‘The old man – die to self‘.
5 Therefore put to death your members which are on the earth: fornication, uncleanness, passion, evil desire, and covetousness, which is idolatry. 6 Because of these things the wrath of God is coming upon the sons of disobedience, 7 in which you yourselves once walked when you lived in them. 8 But now you yourselves are to put off all these: anger, wrath, malice, blasphemy, filthy language out of your mouth. 9 Do not lie to one another, since you have put off the old man with his deeds,
Colossians 3.5-9

Mortify (put to death)therefore your members.
When I looked up the Greek word for mortify it’s nekroo, which means ‘to make dead, nullify, subdue’.

It has a very strong meaning. It almost has the imagery of putting to death and exterminating the old way of life.
13 For if you live according to the flesh you will die; but if by the Spirit you put to death the deeds of the body, you will live.
Romans 8.13

You see brothers and sisters, if we feed sin and feed the loves of flesh, we give it a position in our lives. But that’s the old man, that’s the old way of life, that’s the way of the world.
That’s the way the world is but, as the new man, as a new creation granted in Christ, we are to mortify therefore your members, to take control of our bodies.
Then, it lists certain things: fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness. These are all sexual sins.
Do you see? Satan knows how to entrap man, and he’s been doing it for thousands of years. He knows these things entrap man.
Fornication. Fornication is a sex outside marriage.

Uncleanness (impurity) is a wider word. It could be anything to do with the misuse of sex. Uncleanness is the misuse of sex.
And evil concupiscence (passionate evil desire), I didn’t know what this word meant so I looked it up and it means ‘evil, strong sexual desire’.

These are the things of the old man. These should not be seen in the believer. These things need to be put to death by the power of the Holy Spirit.
The wrath of God is coming upon the children of disobedience.
Why? Because all these things are what the world does and they lead to death.
You may be reminded of James 2.10. It says,
10 For whoever shall keep the whole law, and yet stumble in one point, he is guilty of all.
James 2.10
And of Hebrews 9.22,
22 And according to the law almost all things are purified with blood, and without shedding of blood there is no remission.
Hebrews 9.22
You see brothers and sisters, without putting our faith in the saving work of Jesus Christ, we would be guilty of rebellion against God and deserve death.
This is the old man brothers and sisters, in which you yourself once walked when you lived in them.
We once walked in these sins, we were once in rebellion against Christ. But when we accepted Jesus Christ as our Lord and Saviour, we were freed from them.
And the scripture then goes on:
anger, wrath, malice, blasphemy, filthy language out of your mouth. Do not lie …
These are the things which primarily on what we say, what we do.
James 1.26 says,
26 If anyone among you thinks he is religious, and does not bridle his tongue but deceives his own heart, this one’s religion is useless.
James 1.26
You see brother? It says we are ‘to put off the old man’. It uses this word of ‘putting off’, ‘taking off this old man’ and ‘putting on the new man’.
In summary, from verses 5 to 9, dying to self, we are to mortify our members, take control and bring them under obedience in Christ.
There should be no fornication, uncleanness, and inordinate affection in the believer.
Anger, wrath, malice, blasphemy, filthy language out of your mouth shouldn’t be seen in the believer.
That is the ‘old man’.
We should die to self. It says, ‘put off’ your ‘old man’, repent of your old ways, and follow Christ.
Only by the power of the Holy Spirit will we be able to ‘put off the old man’ and establish our identity is in Christ Jesus.