Charles H. Spurgeon on Psalms 19:13

"Keep back thy servant," etc. Even all the people of God, were they not kept by God's grace and power, they would every moment be undone both in soul and body. It is not our grace, our prayer, our watchfulness keeps us, but it is in the power of God, his right arm, supports us; we may see David praying to God that he would "keep" him in both these respects from temporal dangers (Psalm 18:8, 9; "keep me",) etc.; where he doth not only pray to be kept, but he doth insinuate how carefully God keeps his people, and in what precious account their safety is, even as "the apple of the eye," and for spiritual preservation he often begs it. Though David be God's "servant" yet he will, like a wild horse, run violently, and that into "presumptuous sins," if God "keep" him not "back," yea, he prayeth that God would "keep" the particular parts of his body that they sin not: "keep the door of my lips" (Psalm 141:3); he entreateth God to "keep" his lips and to set a watch about his mouth, as if he were not able to set guard sure enough: thus much more are we to pray that God would "keep" our hearts, our minds, our wills, our affections, for they are more masterful. —Anthony Burgess.