"covers his sins." This is the opposite of confessing and forsaking sins, and is spoken of as covering sins rather than bringing them into the open (See: [[rc://en/ta/man/translate/figs-metaphor]])
This can be stated in active form. Alternate translation: "God will show mercy to the one who confesses and forsakes them" (See: [[rc://en/ta/man/translate/figs-activepassive]])