The first part begins with knowing God, a covenantal knowing rooted in an intimate relationship with Him, and then hears His call: be holy, for I am holy. God alone is the Holy One, and His holiness speaks of His righteousness, moral excellence, fidelity and transcendence. Because He dwells among His people, He sets them apart for Himself, calls them to separate from sin and uncleanness, and makes them vessels for honor, useful to the Master.
The second part turns to sanctification. The believer is saved not only from the guilt of sin but also from its pollution, and God’s will is our sanctification. Holiness means an inner separation from the old nature and an outer separation from evil practices. The law gives the pattern of holy living, the Spirit writes it on the heart, and regeneration begins a growth in which God works in us both to will and to work.