(Isa. 9:2; D&C 138:18)
The land of the shadow of death is a land peopled by those who do not know Jesus Christ, the “great light,” and his gospel. These people walk in darkness. Jesus was the great light that shone upon the inhabitants of Galilee during his mortal mission. Matthew 4:13–16 contains the fulfillment of this prophecy found in Isaiah 9:1–2. As those who follow Christ walk through mortality in the latter days, they will receive great hope, comfort, and joy when they accept Jesus as the “great light.”
(Donald W. Parry, Visualizing Isaiah [Provo, Utah: The Foundation for Ancient Research and Mormon Studies, 2001], 78.)