That touching testimony—and indeed the entire sermon given us by Lehi—becomes more immediate when we realize that a general doctrine of probation for all mankind is reduced to a specific probationary period for each of us personally. Lehi skillfully brought what could be a rather abstract doctrine right down to the "three score and ten years" (or whatever we may be given) of a brief lifetime in which we must learn the gospel, exercise our agency in claiming its promises, and thereby take advantage of "the merits, and mercy, and grace of the Holy Messiah."
What Lehi's "good part" consists of and what the "words of the prophet[s]" taught him is that Christ would be born "with healing in his wings" to overcome the effects of the Fall and to offer to every human soul the privilege of exaltation. That Lehi taught this so well to his children is perhaps best evidenced in the discourse his son Jacob gave to the Nephites at the request of his other son Nephi. Continuing these same doctrinal insights taught by his father on the relationship of the Fall to the Atonement, Jacob said of Christ's coming: "I know that ye know that in the body he shall show himself unto those at Jerusalem, from whence we came; for it is expedient that it should be among them; for it behooveth the great Creator that he suffereth himself to become subject unto man in the flesh, and die for all men, that all men might become subject unto him.
"For as death hath passed upon all men, to fulfil the merciful plan of the great Creator, there must needs be a power of resurrection, and the resurrection must needs come unto man by reason of the fall; and the fall came by reason of transgression; and because man became fallen they were cut off from the presence of the Lord.
"Wherefore, it must needs be an infinite atonement—save it should be an infinite atonement this corruption could not put on incorruption. Wherefore, the first judgment which came upon man must needs have remained to an endless duration. And if so, this flesh must have laid down to rot and to crumble to its mother earth, to rise no more."
Clearly teaching that Christ died for "all men," Jacob was the first in the Book of Mormon to use the phrase infinite atonement, one of the truly essential characteristics of the doctrine of the Atonement as taught in this volume of scripture. Amulek reinforced that doctrine later with his own witness of the scope and breadth of Christ's sacrifice. Because the sins, transgressions, and heartaches of mankind are so universal, he said, "I do know that Christ shall come among the children of men, to take upon him the transgressions of his people, and that he shall atone for the sins of the world; for the Lord God hath spoken it.
"For it is expedient that an atonement should be made; for according to the great plan of the Eternal God there must be an atonement made, or else all mankind must unavoidably perish; yea, all are hardened; yea, all are fallen and are lost, and must perish except it be through the atonement which it is expedient should be made.
"For it is expedient that there should be a great and last sacrifice; yea, not a sacrifice of man, neither of beast, neither of any manner of fowl; for it shall not be a human sacrifice; but it must be an infinite and eternal sacrifice. . . .
"Therefore there can be nothing which is short of an infinite atonement which will suffice for the sins of the world."
Because the Fall was universal, with spiritual and physical death coming to all of God's children, so too must the Atonement be universal. Jacob taught that its unconditional aspects would cover all mankind—non-Christians as well as Christians, the godless as well as the God-fearing, the untaught infant as well as the fully converted and knowledgeable adult: "He cometh into the world that he may save all men if they will hearken unto his voice; for behold, he suffereth the pains of all men, yea, the pains of every living creature, both men, women, and children, who belong to the family of Adam.
"And he suffereth this that the resurrection might pass upon all men, that all might stand before him at the great and judgment day."