Alvin Smith died some five years before the restoration of the priesthood, but he had accepted his brother Joseph’s testimony of the First Vision. Speaking of his oldest brother, Alvin, Joseph said, “He was … one of the noblest of my father’s family. He was one of the noblest of the sons of men … In him there was no guile … He was one of the soberest of men, and when he died the angel of the Lord visited him in his last moments” (History of the Church, 5:126-27).
The Lord revealed the doctrine of priesthood ordinances for the dead
Since Alvin’s death, the gospel restoration has made available the saving ordinances as part of the fullness of the gospel. Because the Saints can function as proxies for deceased family members, we can provide the temple ordinances for all those who were unable to receive those saving ordinances in their mortal lifetime.