Thought From Today’s Old Testament Passage:
[Psalm 19:12-13] All the discoveries of sin made to us by the law should drive us to the throne of grace, there to pray, as David does here, (1.) For mercy to pardon. Finding himself unable to specify all the particulars of his transgressions, he cries out, Lord, cleanse me from my secret faults; not secret to God, so none are, nor only such as were secret to the world, but such as were hidden from his own observation of himself. The best of men have reason to suspect themselves guilty of many secret faults, and to pray to God to cleanse them from that guilt and not to lay it to their charge; for even our sins of infirmity and inadvertency, and our secret sins, would be our ruin if God should deal with us according to the desert of them. Even secret faults are defiling, and render us unfit for communion with God; but, when they are pardoned, we are cleansed from them, 1 Jn. 1:7. (2.) For grace to help in time of need. Having prayed that his sins of infirmity might be pardoned, he prays that presumptuous sins might be prevented, v. 13. All that truly repent of their sins, and have them pardoned, are in care not to relapse into sin, nor to return again to folly, as appears by their prayers, which concur with David’s here, … "Keep me from ever being guilty of a wilful presumptuous sin.’’ We ought to pray that we may be kept from sins of infirmity, but especially from presumptuous sins, which most offend God and wound conscience, which wither our comforts and shock our hopes.
Matthew Henry, Matthew Henry’s Commentary on the Bible (Peabody, MA: Hendrickson Publishers), 1997 (computer file)