Alma 60:13

for the Lord suffereth the righteous to be slain, that his justice and judgement may come upon the wicked; therefore ye need not suppose that the righteous are lost because they are slain; but behold, they do enter into the rest of the Lord their God.

The Lord lets good people be killed so his justice can come on the bad people. So don’t think good people are lost because they are killed. They go to rest with the Lord their God.

The Lord allows the righteous to be killed so his justice can fall on the wicked. Don’t assume the righteous are lost just because they’re slain. They enter into the rest of the Lord their God.