It's a great question you've asked.
The answer to this is, be who we are, not who we were.
Scripture is replete with these two facts, that we have been recreated in righteousness and true holiness. And that we may even so live according to the manner of our former lives, before we were reborn into life, while we yet walked in death.
1 Peter 1:13-16 KJV
13) Wherefore gird up the loins of your mind, be sober, and hope to the end for the grace that is to be brought unto you at the revelation of Jesus Christ;
14)
As obedient children, not fashioning yourselves according to the former lusts in your ignorance:
15) But as he which hath called you is holy, so be ye holy in all manner of conversation;
16) Because it is written, Be ye holy; for I am holy.
He is holy, and it's His life that lives in us.
Ephesians 4:20-25 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
(conduct or manner of living) 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.
There is so much in this chapter, and even these few verses, but just to say, having been created patterned after God Himself, which is described as "righteousness and true holiness", this is now what we are. The inner man lives in the light and life of God.
But the Apostle goes on, "Wherefore putting away lying, speak every man truth with his neighbor". Why does he have to tell us to stop lying? It's because we continue to fashion ourselves according to our former lusts. We are members one of another, this is God's design, He's baptized us into Christ, into one body, and we are members of one other.
Righteousness is to do the right think, to rejoice in righteousness. In this case, to speak truth.
Holiness is to be set apart for God's exclusive use. He's made us members one of another, when we live as members of one another, we are living out the holiness that God created in us.
At the heart is the renewing of the mind. ". . . and be renewed in the spirit of your mind . . ."
Romans 12:1-2 KJV
1) I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service.
2) And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.
"Be not conformed to this world", this is middle/passive voice, I think in this context it's middle, that we do this to ourselves. The word here, conformed, is from the word we get "schematic" from. Not that a derived word always carries the original meaning, it doesn't. But in this case it refers to the pattern of things.
This is like what Peter wrote, not fashioning yourselves according to your former lusts.
Ephesians 2:2-3 KJV
2) Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience:
3) Among whom also we all had our conversation in times past in the lusts of our flesh, fulfilling the desires of the flesh and of the mind; and were by nature the children of wrath, even as others.
"Be ye transformed", this is the passive voice, this is done to us, we do not do this ourselves. By the renewing of your mind.
Philippians 2:12-13 KJV
12) Wherefore, my beloved, as ye have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling.
13) For it is God which worketh in you both to will and to do of his good pleasure.
It's God working in us so that we both want to do, and are able to do what pleases Him.
Philippians 2:14-16 KJV
14) Do all things without murmurings and disputings:
15) That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world;
16) Holding forth
the word of life; that I may rejoice in the day of Christ, that I have not run in vain, neither laboured in vain.
What this world needs is not to see me, but to see Jesus through me, as I live according to Christ's life in me, not following my previous and habitual way of life.
There is plenty reason for me to believe this will continue all my life, but on the other hand, I know that God can sanctify our lives to whatever degree He intends, so I don't limit Him.
Our part is firstly to trust Jesus for everything that needs to be done, and secondly to do all those things that we are able to do in obedience to what God wants in our lives.
There is so much more to say but I'll stop here for now.
Much love!