1 Nephi 19:23 is the second scripture mastery. It reads "And I did read many things unto them which were written in the books of Moses; but that I might more fully persuade them to believe in the Lord their Redeemer I did read unto them that which was written by the prophet Isaiah; for I did liken all scriptures unto us, that it might be for our profit and learning."
Application to my life: The reason we have the scriptures now days is also for our profit and learning. Sometimes I think, "Hmm now how is this event that happened a long long long time ago have anything to do with my life today?" The truth is there is so many ways that the scriptures help me in my life. I may not have to part the sea or go back and get plates but I still have to have faith in all the standards I am asked to keep. Seminary is such a great experience because it really does teach me to apply the scriptures to my life and be for my profit and learning.