He knows the depth of sorrow

Jacob placed no qualifiers when he said the Savior would suffer "the pains of every living creature, both men, women, and children, who belong to the family of Adam" (2 Nephi 9:21). These were pains both related and unrelated to sin or transgression. In other words, the Savior voluntarily took upon himself not only the cumulative burden of all sin and transgression, but also the cumulative burden of all depression, all loneliness, all sorrow, all mental, emotional, and physical hurt, and all weakness of every kind that afflicts mankind. He knows the depth of sorrow that stems from death; he knows the widow's anguish. He understands the agonizing parental pain when children go astray; he has felt the striking pain of cancer and every other debilitating ailment heaped upon man. Impossible as it may seem, he has somehow taken upon himself those feelings of inadequacy, sometimes even utter hopelessness, that accompany our rejections and weaknesses. There is no mortal condition, however gruesome or ugly or hopeless it may seem, that has escaped his grasp or his suffering. No one will be able to say, "But you don't understand my particular plight." The scriptures are emphatic on this point - "he comprehended all things" because he decended below all things" (D&C 88:6; see also D&C 122:8).


Tad R. Callister, The Infinite Atonement. 2000. p.104