If we still have sin we are liars, if we cast out the lying spirit, we cease to lie.The way the understanding comes is through the spiritual gifts of 1 Corinthians 12 ( or the gifts the OT prophets used).
The gifts in people are just that. Gifts that work inside a persons spirit. The wretched man still exists. The old man that the dominion of sin no longer exists, but occasional sin does happen. It should not happen but scripture says we lie if we say we have no sin.
If I get a correct understanding:
It is not a supper eddif
The truth comes by the Holy Spirit
The spiritual gifts are to help us witness. They do not make us holy. are we changed? Yes. Is there another better change at the last trump? Absolutely.
I am righteous through what Jesus did.
To help convey that to others we receive gifts of the Holy Spirit. We still walk-in this body of death. At the resurrection perfection comes.
So
The man I am is imperfect, and sees through a glass darkly
But
The Holy Spirit can provide knowledge beyond the redneck I am.
Also others fill in knowledge and watch out to keep me straightened out.
eddif
If we reach the stature of Christ, in HIs fulness of God in full assurance of faith, we are o0ne with Christ, we cant be one with Christ, ( perfect as one together/put on Christ/charity, the bond of perfectness) when the love of God is not perfected in us.
Likewise we did see darkly, now we see as told..
Ephesians 1:17 That the God of our Lord Jesus Christ, the Father of glory, may give unto you the spirit of wisdom and revelation in the knowledge of him:
18 The eyes of your understanding being enlightened; that ye may know what is the hope of his calling, and what the riches of the glory of his inheritance in the saints,
Ephesians 3:17 That Christ may dwell in your hearts by faith; that ye, being rooted and grounded in love,
18 May be able to comprehend with all saints what is the breadth, and length, and depth, and height;
19 And to know the love of Christ, which passeth knowledge, that ye might be filled with all the fulness of God.
Ephesians 4:13 Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ: