The Book of Mormon is All About Joy

Joy.

Joy and rejoicing everywhere.

That's what the Book of Mormon is about: how to receive joy beyond our wildest imaginations!

"Men [and women] are that the might have joy" (2 Nephi 2:25).

We exist to be happy.

And how?

It's receiving Christ ourselves through repentance and helping others receive Him as well -- through repentance.

this is joy which none receiveth save it be the truly penitent and humble seeker of happiness. (Alma 27:18) 

I like the thought of God's light shining inside of us: 

their souls were illuminated by the light of the everlasting word; (Alma 5:7)

I think that when we have God's light in us, we feel joy.  It's delicious to us. 

It's like the fruit in Lehi's vision of the tree of life (1 Nephi 8:10-12):

And it came to pass that I beheld a tree, whose fruit was desirable to make one happy. 

And it came to pass that I did go forth and partake of the fruit thereof; and I beheld that it was most sweet, above all that I ever before tasted. Yea, and I beheld that the fruit thereof was white, to exceed all the whiteness that I had ever seen.

And as I partook of the fruit thereof it filled my soul with exceedingly great joy; wherefore, I began to be desirous that my family should partake of it also; for I knew that it was desirable above all other fruit. 

 The Book of Mormon: Another Testament of Jesus Christ teaches us how to be happy through faith in the Lord Jesus Christ and repentance.  As I've tasted a bit of that happiness, I rejoice.  I count myself lucky, blessed beyond measure to have this great gift.