1 Nephi 19:21

And he surely did show unto the prophets of old all things concerning them;

and also he did show unto many concerning us;

wherefore, it must needs be that we know concerning them

for they are written upon the plates of brass.

wherefore, it must needs be that we know concerning them

must - 9 occurrences in 7 verses - 1 Nephi 16:35,   17:3, 25, 43,   18:15,   19:12, 21