Mormon had his own Sacred Grove experience. At the age of fifteen, the Lord made it clear to him that he was no ordinary teenager. This is according to the Lord’s pattern. He often calls prophets while in their youth. Such was the case with Joseph Smith, Nephi, Jacob, Enoch, Samuel, and others (see JS-H 1:7, 1 Nephi 2:16, 2 Nephi 2:4, Moses 6:31, and 1 Sam 3:1-10). One can only imagine how such an experience would have molded the behavior and broadened the perspective of an already sober youth.
“There must be something significant … concerning the stage of life one goes through at the age of about 14. Mormon’s awakening to spiritual matters at about this age foreshadows a similar awakening at a similar age by the young Joseph Smith, who would translate Mormon’s record… . Similarly, through modern-day prophets, the Lord has specified 12 as the age when worthy young men of His Church can receive the Aaronic Priesthood. What all of this seems to suggest is a heightened spiritual sense experienced at about this age - something that conscientious parents of young teenagers would do well to keep in mind.” (E.D. Clark & R. S. Clark, Fathers and Sons in the Book of Mormon, as taken from Church News, 10/24/92)