With reference to the words of his father Lehi, Nephi declares that he had "great desires to know of the mysteries of God" and that he "did cry unto the Lord and behold he did visit me" (1 Nephi 2:16). He then quotes the Lord as saying to him: "And as much as ye shall keep my commandments, ye shall prosper, and shall be led to a land of promise; yea, even a land which I have prepared for you; yea, a land which is choice above all other lands" (1 Nephi 2:20). Nephi also stated that when he returned from speaking with the Lord he entered the tent of Lehi, who then told Nephi that he had had a dream that Nephi and his brothers needed to return to Jerusalem to acquire the plates of Laban which contained a record of the Jews and the genealogy of Lehi's forefathers (1 Nephi 4:13-14).
According to Potter and Wellington, it seems reasonable to assume that at this point in time, both Nephi and his father realized that they would not be returning to live in Palestine, thus the need for the plates of brass. It would also seem likely that Lehi shared this information with the entire family, for Nephi, in rallying his brothers for a second attempt in acquiring the plates from Laban, reminded them that the plates would be necessary "that we may preserve unto our children the language of our fathers" (1 Nephi 3:18-19) However, it is not certain if Lehi's party knew at this point that they would be traveling the length of Arabia and building a ship large enough to take them to a land of promise across the many waters. One should keep in mind that in the years that surrounded the Babylonian destruction of Jerusalem, many other Jews fled into central Arabia seeking new homes far from the persecutions of King Nebuchadnezzar. There were many Jewish settlements in Saudi Arabia, Dedan, Khaibar, and Medina (Qura'Arabiyyah) in that era which indicate that other migration parties from Palestine entered Arabia looking for a "land of promise" in its wilderness. [George Potter and Richard Wellington, Discovering The Lehi-Nephi Trail, Unpublished Manuscript, 2000, p. 70] [See the commentary on 1 Nephi 13:12]; 17:36-38; 2 Nephi 1:5; Ether 2:8]