President David O. McKay always taught that in the control of morals there must be self-mastery, self-discipline, and self-control.

President Joseph F. Smith said, “No man is safe unless he is master of himself, and there is no tyrant so merciless or more to be dreaded than an uncontrollable appetite or passion.” (Gospel Doctrine [Bookcraft, 1939], p. 247.)

The Savior warned, “Watch and pray, that ye enter not into temptation: the spirit indeed is willing, but the flesh is weak.” (Matt. 26:41.) – Delbert L. Stapely, “Our Responsibility: To Save the World,” Ensign (CR) November 1971