Mosiah 28:4

And thus did the spirit of the Lord work upon them, for they were the very vilest of sinners. And the Lord saw fit in his infinite mercy to spare them; nevertheless they suffered much anguish of soul, because of their iniquities; and suffering much, fearing that they should be cast off forever.

The Spirit of the Lord worked on them like this because they had been the worst sinners. The Lord was kind and let them live. But they felt terrible in their souls because of their sins. They suffered a lot. They were afraid they would be cut off from God forever.

This was how the Spirit of the Lord worked in them. They’d once been terrible sinners—the worst kind—and God in his endless mercy had spared them. Even so, they’d suffered deeply for what they’d done. They’d lived in constant fear that God might cast them away forever. They knew what that terror felt like.