Charles H. Spurgeon on Psalms 19:13

To sin presumptuously is the highest step. So in David's account; for first he prays, "Lord, keep me from secret sins," which he maketh sins of ignorance, and then next he prays against "presumptuous sins," which, as the opposition shows, are sins against knowledge; for says he, "if they get dominion over me, I shall not be free from that great offence," that is, that unpardonable sin which shall never be forgiven: so as these are nearest it of any other, yet not so as that every one that falls into such a sin commits it, but he is nigh to it, at the next step to it. For to commit that sin, but two things are required —light in the mind, and malice in the heart; not malice alone, unless there be light, for then that apostle had sinned it, so as knowledge is the parent of it, it is "after receiving the knowledge of the truth." Hebrews 10:27, 28. —Thomas Goodwin.