20 There shall be no more thence an infant of days, nor an old man that hath not filled his days: for the child shall die an hundred years old; but the sinner being an hundred years old shall be accursed.
The Doctrine and Covenants, Section 101:29-31
29 And there shall be no sorrow because there is no death.
30 In that day an infant shall not die until he is old; and his life shall be as the age of a tree;
31 And when he dies he shall not sleep, that is to say in the earth, but shall be changed in the twinkling of an eye, and shall be caught up, and his rest shall be glorious.
The Doctrine and Covenants, Section 63:50-51
50 And he that liveth when the Lord shall come, and hath kept the faith, blessed is he; nevertheless, it is appointed to him to die at the age of man.
51 Wherefore, children shall grow up until they become old; old men shall die; but they shall not sleep in the dust, but they shall be changed in the twinkling of an eye.