Literary: These two verses follow very closely the Isaiah text:
Isa. 29:17
17 Is it not yet a very little while, and Lebanon shall be turned into a fruitful field, and the fruitful field shall be esteemed as a forest?
18 ¶ And in that day shall the deaf hear the words of the book, and the eyes of the blind shall see out of obscurity, and out of darkness.
In both Isaiah and Nephi, the reference to Lebanon as a fruitful field is a reference to the events of the end time. For Nephi specifically, he is placing the coming of the Book of Mormon in the general timeframe of the “last days.”