Mosiah 4:30
But this much I can tell you, that if ye do not watch yourselves, and your thoughts, and your words, and your deeds, and observe the commandments of God, and continue in the faith of what ye have heard concerning the coming of our Lord, even unto the end of your lives, ye must perish. And now, O man, remember, and perish not.
“There is no recess in the struggle to discipline and school our spirits. Ours is the struggle of a lifetime. Even to the New World Twelve, Christ said: ‘Ye must watch and pray always, lest ye be tempted by the devil, and ye be led away captive by him’ (3 Nephi 18:15).” (Joseph Fielding McConkie and Robert L. Millet, Doctrinal Commentary on the Book of Mormon, 4 vols. [Salt Lake City: Bookcraft, 1987-1992], 2: 168.)