Psalms 38:18 - Matthew Poole's English Annotations on the Holy Bible

Declare mine iniquity; either to thee; or publicly to the world, because my sin hath been public and scandalous. I will be sorry, Heb. I will be (or, I am; futures being oft so taken) solicitous or anxious; full of grief for what is past, and of cares and fears for the future; partly lest I should relapse into the same folly upon new temptations; and partly lest thou shouldst cut me off for my sins. Therefore pity, and pardon, and save me. For my sin; or, by reason of my sin, or upon that occasion.