Psalms 19:13

For sins committed -in error," (A.V. through ignorance) and for -hidden" offences, the ceremonial law provided an atonement (Leviticus 4:1 ff., Leviticus 4:13 ff; Leviticus 5:2 ff.; Numbers 15:22 ff.); but for sins committed -with a high hand," in a spirit of proud defiance, there was no atonement (Numbers 15:30-31). From such presumptuous sinshe prays to be restrained, as David was once restrained from a desperate act of revenge (1 Samuel 25:39). Such sins soon become a man's masters, and he becomes their slave (John 8:34). They rule over him, instead of his ruling over them (Genesis 4:7). For presumptuous, lit. proud, cp. presumptuously, lit. in pride, Exodus 21:14; Deuteronomy 17:12-13.

Then (he continues) if Thou dost grant me this grace, shall I be perfect, heart-whole with Thee (Psalms 18:23), and I shall be clear from great transgression, innocent of the deadly sin of rebellion (Isaiah 1:2) and apostasy from Jehovah.

But the word rendered - presumptuoussins" everywhere else means - proudmen," and this may be its meaning here. The Psalmist prays to be saved from the oppression of the proud and godless, lest he should be tempted even to deny God. Cp. Psalms 119:121-122; and note how often "the proud" are mentioned in that Psalm, and how the thought of faithfulness to the Law in the teeth of mockery and persecution is emphasised (Psalms 119:51; Psalms 119:69; Psalms 119:78; Psalms 119:85-87).