"and turn to the Lord." Here "turn" is a metaphor for starting to obey the Lord. Alternate translation: "and start obeying the Lord" (See: [[rc://en/ta/man/jit/figs-metaphor]])
Here "blotted out" is a metaphor for forgiving. Sins are spoken of as if they are written in a book and God erases them from the book when he forgives them. This can be stated in active form. Alternate translation: "so that God will forgive you for sinning against him" (See: [[rc://en/ta/man/jit/figs-activepassive]] and [[rc://en/ta/man/jit/figs-metaphor]])