The Lord’s broad spectrum of available communication methods ranges from his voice coming into the mind, as with Enos (Enos 1:10), all the way to the visions and manifestations granted to seers such as Enoch (Moses 7) or Joseph Smith (D&C 137).
Indeed, it seems it is the powers of seership that are brought into play in many of the outstanding revelations the scriptures record, of which this vision of Lehi’s was one. “Seers and prophets,” said Joseph Smith, “saw the mysteries of godliness; they saw the flood before it came; ... they saw the stone cut out of the mountain, which filled the whole earth; they saw the Son of God come from the regions of bliss and dwell with men on earth; they saw the glory of the Lord when he showed the transfiguration of the earth on the mount; they saw truth spring out of the earth, and righteousness look down from heaven in the last days, before the Lord came the second time to gather his elect.” (Teachings, pp. 12-13.)
This accords with Ammon’s expressions that “a seer can know of things which are past and also of things which are to come, and by them ... shall secret things be made manifest” (Mosiah 8:17).