Alma 40:12

12 And then shall it come to pass, that the spirits of those who are righteous are received into a state of happiness, which is called paradise, a state of rest, a state of peace, where they shall rest from all their troubles and from all care, and sorrow.

Neal A. Maxwell (Quorum of the Twelve)

Some derive from these words that rest means no work and merely languid passivity. In fact, the rest described is from the troubles, cares, and sorrows of this world.

To begin with, a certain peacefulness and restfulness will occur in paradise, because the faithful will see things with a more complete, restful, and reassuring perspective. Nonetheless, the faithful will soon be caught up fully and be "anxiously engaged" in the vast work underway in al the spirit world (D&C 58:27). So many of the cares and demands of the of the world which press upon us here and now, including doing the chores of this world, will not dominate us there. Hence, paradise will be, comparatively, "a state of peace." Furthermore, the spirit body will not suffer certain of the ills and constraints which now beset the mortal body. The result will be added zestfulness there, as described by Elder John Taylor: "[Death] this dark shadow and valley is so trifling . . . [one is] passed from a state of sorrow [and] grief, . . . into a state of existence where I can enjoy life to the fullest extent as far as that can be done without a body. . . . I thirst no more, I want to sleep no more, I hunger no more, I tire no more, I run, I walk, I labor, . . . nothing like pain or weariness, I am full of life, full of vigor" ("Discourse by Elder John Taylor." Deseret News, 28 July 1874, p. 1). (The Promise of Discipleship, p. 106)

Joseph Fielding Smith (Quorum of the Twelve)

It is the righteous who go to paradise. It is the righteous who cease from those things that trouble.... The righteous, those who have kept the commandments of the Lord, ... are in happiness in paradise. They cease from all this trouble, and trial, and tribulation, and anguish of soul. They are free from all these torments, because they have been true and faithful to their covenants. (Doctrines of Salvation, 2:229-230)