1 Nephi 12:23

And it came to pass that I beheld, after they had dwindled in unbelief

they became a dark, and loathsome, and a filthy people,

full of idleness and all manner of abominations.

And it came to pass that I beheld, after they had dwindled in unbelief

unbelief - 4 occurrences in 4 verses - 1 Nephi 10:11,   12:22, 23,   13:35