To be clear, Sanctification in Scripture is not the slow moral self‑improvement project most Christians imagine; it is the act of God setting a person apart by giving them a new heart, a new nature, and a new allegiance before they ever believe. In both Testaments, sanctification is God’s decisive, creative work: He cuts away the old heart (circumcision of the heart), gives a new spirit, and claims a people as His own possession. This is why Paul can say believers are “sanctified in Christ Jesus” *before* he ever addresses their behavior. In biblical logic, sanctification precedes justification because God must first make a person *alive*, *clean*, and *His* in order for them to respond in faith. The new heart is the root; faith is the fruit; justification is the legal declaration that follows. Moral transformation comes downstream, not as the engine of sanctification but as its evidence. True sanctification is God’s sovereign act of creating a people who will believe, not a spiritual technique for becoming ethically competent.