8 But there is a resurrection, therefore the grave hath no victory, and the sting of death is swallowed up in Christ.
9 He is the light and the life of the world; yea, a light that is endless, that can never be darkened; yea, and also a life which is endless, that there can be no more death. (Mosiah 16:8-9, emphasis added)
That image of Christ as the light that can never be darkened is more meaningful if you remember the prophet lived in a time when light only came from burning fuel. A light that is never darkened is a light that never lacks fuel, though nobody knows where the fuel comes from. It keeps burning on its own, and that is a great metaphor for how the resurrected Christ (and someday us) keeps living in glory.
This hope of resurrection is the great thing that gives us reason to believe, to repent, to do everything we can to become better so we can be ready for eternity.