Textual: This reference echoes the ideas found in Mark 9:12: “And he answered and told them, Elias verily cometh first, and restoreth all things; and how it is written of the Son of man, that he must suffer many things, and be set at nought.” Alma is very certainly citing some previous Old Testament or Book of Mormon author rather than Mark, but we do not have the particular reference that he is citing.
Alma has a very interesting take on the nature of Jesus’ suffering. For Alma the “pains and afflictions” refer to his mortality, and his complete subjection to mortality. As a human, Jesus, suffered pain when bruised, and illnesses. For Alma these become symbolic of the sacrificial atonement for pains and sicknesses. Jesus endures them to remove them from the people. In this he appears to be echoing the idea expressed in Genesis:
“Ex. 23:25 And ye shall serve the LORD your God, and he shall bless thy bread, and thy water; and I will take sickness away from the midst of thee.”
For Alma, this is not an expiation for sin, but rather a removal of the pains and illnesses. In this context, the reference to Christ’s earthly mission would be to the miraculous healings rather than the experience in Gethsemane.