Main point summary
God expects believers to live each moment in a way that reflects the awesome change wrought in them when they believed the Gospel.
Cf. Eph. 2:1-3 The walk of the Christian should not look anything like the walk of those who are still dead in trespasses and sins. This is not a matter of preference or personal standard - it is a command of the Lord.
Cf. 2 Cor. 4:4-6 Satan blinds men's minds - But God illuminates them by the Gospel. What a contrast!
Cf. 2 Cor. 5:17-18 Christianity is not merely a change of mind or behavior. The believer is a totally new creation, owing everything to the grace of God (cf. 2 Cor. 4:6).
Cf. I John 1:5 The Lord taught that God is totally holy and can not have fellowship with darkness. Christ's teachings were recorded by the apostles and have been preserved for us today. We know exactly what Christ wants us to know. (cf. 2 Tim. 3:16-17)
Cf. Col. 3:5-14 ; Rom. 6:11-18; Gal. 5:16-25 This important teaching is repeated throughout the N.T. Putting off the old is not enough - we must at the same time put on the new.
Cf. Rom. 12:1-2 Believers need to submit themselves to God in holiness and resist the conforming pressures of this evil world.
Cf. Rom. 1:18-32 Man is in this degraded condition because he refused to glorify God when he knew Him. Once the Creator's authority is rejected, His creation can only sink lower and lower in sin and degradation.
This I say therefore, and testify in the Lord,
In light of what was just said , I am commanding you on behalf of the Lord...
that ye henceforth walk not as other Gentiles walk,
This command is that you would no longer live your everyday lives like the unsaved Gentile world does
in the vanity of their mind,
They conduct themselves along, having an empty, pointless mindset,
Having the understanding darkened,
This is because their minds remain in a state of spiritual darkness, lacking the light of true understanding...
being alienated from the life of God
Not only that, but they are also separated from the spiritual life that only God can give...
through the ignorance that is in them,
this state of spiritual death is being prolonged as a result of their spiritual ignorance...
because of the blindness of their heart:
...that is caused by their hardened, calloused, unrepentant hearts.
Who being past feeling have given themselves over unto lasciviousness,
These individuals have become so desensitized that they have given themselves over to a life of sensuality
to work all uncleanness with greediness.
... in order to greedily indulge themselves in all forms of uncleanness.
But ye have not so learned Christ;
That may be common in the world around you, but this is not how Christ would have you live...
If so be that ye have heard him, and have been taught by him, as the truth is in Jesus:
You truly have heard the teachings of Christ and have received instruction from the One who is the Truth!
That ye put off concerning the former conversation the old man,
The content of His message is this: You need to constantly put aside the lifestyle that comes from the old, sinful nature...
which is corrupt according to the deceitful lusts;
...that nature is defiled because it is constantly acting upon its deceitful desires to do evil.
And be renewed in the spirit of your mind;
This calls for a totally new way of thinking, one totally opposed to the old fleshly mindset...
And that ye put on the new man,
This new spiritual mindset will lead you to continually take up the lifestyle that is produced by the new spiritual nature...
which after God is created in righteousness and true holiness.
...the nature that has been patterned after God, a nature of righteousness and true holiness.