… What does it mean to enter into the rest of the Lord? Speaking for myself, it means that through the love of God I have been won over to Him, so that I can feel at rest in Christ, that I may no more be disturbed by every wind of doctrine, by the cunning and craftiness of men, whereby they lie in wait to deceive; and that I am established in the knowledge and testimony of Jesus Christ, so that no power can turn me aside from the straight and narrow path that leads back into the presence of God, to enjoy exaltation in His glorious kingdom; that from this time henceforth I shall enjoy that rest until I shall rest with Him in the heavens. — Teachings of Presidents of the Church: Joseph F. Smith, Chapter 48: Finding Rest in Christ.
Elder Bruce R. McConkie (1915–1985) taught: “The rest of the Lord, where mortals are concerned, is to gain a perfect knowledge of the divinity of the great latter-day work. [President Joseph F. Smith said,] ‘It means entering into the knowledge and love of God, having faith in his purpose and in his plan, to such an extent that we know we are right, and that we are not hunting for something else; we are not disturbed by every wind of doctrine, or by the cunning and craftiness of men who lie in wait to deceive.’ It is ‘rest from the religious turmoil of the world; from the cry that is going forth, here and there—lo, here is Christ; lo, there is Christ.’ … The rest of the Lord, in eternity, is to inherit eternal life, to gain the fulness of the Lord’s glory. — Elder W. Craig Zwick, “Enter into the Rest of the Lord,” Ensign, February 2012