Mosiah 28:14, 16, 18

14 Now these things were prepared from the beginning, and were handed down from generation to generation, for the purpose of interpreting languages;

Beginning? How beginning? Tower of Babel? Or pre-earth life? Or both?

16 And whosoever has these things is called seer, after the manner of old times.

So Mosiah was a prophet. Why am I feeling like I just learned that for the first time?

18 Now this account did cause the people of Mosiah to mourn exceedingly, yea, they were filled with sorrow; nevertheless it gave them much knowledge, in the which they did rejoice.

Even though knowledge may bring us sorrow, we can rejoice in having the knowledge itself. Knowledge, regardless what of, is rejoiceable.