As faith is the spring and cause of all obedience (for “without faith it is impossible to please God,” and the obedience that is accepted with him is “the obedience of faith”), so is unbelief of all sin. All sins of flesh and spirit have no other root. Did men believe either the promises or threatenings of God, they would not by their sins so despise him and neglect him as they do. And as this is so with respect unto the total prevalency of unbelief, so it is as to its partial efficacy. As our obedience follows in proportion to the operation of our faith, so do all our sins and irregularities answer the working and prevalency of unbelief in us.
– John Owen –
from Owen’s Exposition of Hebrews, volume 4, page 196; William H. Goold edition, printed byBanner of Truth Trust, 2009