8 For God seeks nothing else from us, save a good purpose. Say not, How are my sins blotted out? I tell you, By willing, by believing. What can be shorter than this? But if, while your lips declare you willing, your heart be silent, He knows the heart, who judges you. Cease from this day from every evil deed. Let not your tongue speak unseemly words, let your eye abstain from sin, and from roving after things unprofitable.
Source: Catechetical Lectures (New Advent)