3. Faith is the instrumental cause of our sanctification; so that where it is not, no holiness can be wrought in us. “God purifieth our hearts by faith,” Acts 15:9, and not otherwise; and where the heart is not purified, there is no holiness. All the duties in the world will not denominate him holy whose heart is not purified; nor will any such duties be holy themselves, seeing unto the unclean all things are unclean. All the obedience that is accepted with God is the “obedience of faith,” Rom. 1:5; thence it springs, and therewith is it animated. So is it expressed, 1 Pet. 1:20–22, “You who by Christ do believe in God, and have purified your souls in obeying the truth through the Spirit.” It is from faith in God through Jesus Christ, acting itself in obedience unto the gospel, that we purify or cleanse our souls; which is our sanctification. See Col. 2:12–14, 3:7–11.

—John Owen, The Works of John Owen, ed. William H. Goold, vol. 3 (Edinburgh: T&T Clark, n.d.), 414.