God is the One Who is going to sanctify us entirely (1 Thessalonians 5:23). We can't do it on our own. We have to depend on Him - for He is the One Who works in us giving us both the desire as well as the ability to do His will. But we have to "work out our salvation with fear and trembling" (Philippians 2:12, 13). We have to work out what God works in, for He hasn't turned us into robots!
God cleanses us from the guilt of sin. But we are commanded to "cleanse ourselves from all defilement of flesh and spirit, perfecting holiness in the fear of God" (2 Corinthians 7:1). We have to do this, as and when we get light on any defilement within us.
It is thus, as we "by the Spirit, put to death the deeds of the body" (Romans 8:13) that the fruit of the Spirit - love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control - will become more and more manifest in us. This is what it means to be transformed into the likeness of Christ.
Thus our path will become one of increasing light (Proverbs 4:18). This is the glorious way of sanctification that God has made for us.
Link - https://www.cfcindia.com/books/a-good-foundation