Does Scripture say: "This is God's will, that He Sanctify you." Setting aside your involvement as an unnecessary willful party?
Or does it say: "This is the will of God, your Sanctification...." (Thessalonians 4:3). Expecting you to participate in the death to the right of yourself, equally disposed, as God deals with Sin and we deal with sins in our New Creation? And yet, ironically it is only in the experiences God places before us that we can come to such a personal revelation of ourselves. But as much as we are responsible to act toward God, God is Supernaturally Faithful towards us first.
"But of Him you are in Christ Jesus who became for us Sanctification." (1 Col. 1:30).
Thus, we have a two-sided coin here in Sanctification. We have a death side, and we have a life side. The death side Jesus contends will take our role of will to supply; Christ not withstanding. While the life side takes God's role thru Jesus Christ; our will not withstanding. Sanctification requires our coming to the place of death. (Gal. 2:20): only becomes real and not pretentious when we come to the revelation that we are willing to lay down our lives along side the foot of Jesus at the Cross. After all, this is a relationship, and not a dictatorship, or robotic relationship. We were bought at a price, but we must make our will be freely given thru obedience or it is law once more. Our "Aha" moment of "I have been crucified with Christ, and I no longer live...." Must be our experience as God affords its opportunity.
But many of us spend so much time there we become morbid. There is always a tremendous battle before Sanctification is realized - something within us pushing with resentment against the demands of Christ. When the Holy Spirit begins to show us what Sanctification means, the struggle starts immediately. Jesus said, "If anyone comes to Me and does not hate....his own life....he cannot be My disciple." (Luke 14:26).
On the life side of Sanctification there is a mystery; that the perfect qualities of Jesus Christ are imparted as a gift to me, not gradually, but instantly once I enter by faith into the realization that He "became for (me)....Sanctification...." Sanctification means nothing less than the Holiness of Jesus becoming mine and being exhibited in my life.
Thus, it is coupled with the realness of me being crucified with Christ, and the wonderful secret of living a Holy life unpretentiously, then, not imitating Jesus, but actually and honestly letting the perfect qualities of Jesus exhibit themselves in my human flesh, by way of intentionality to obey Christ from the love of my heart, and nothing else lest it be works, or the law. But this, in no way, lessens the need for the fruit to be evident, in successful obedience wrought out by Christ. In fact, it only increases it by the standards of Christs narrow purity over our own..
Sanctification is, "Christ in you...." (Col. 1:27); not compromised by any rebellion in us; Gods forgiveness thru confession not withstanding by way of need and not by way of inevitability.