1 Nephi 1:1-3 I, Nephi, having been born of goodly parents, therefore I was taught somewhat in all the learning of my father; and having seen many afflictions in the course of my days, nevertheless, having been highly favored of the Lord in all my days; yea, having had a great knowledge of the goodness and the mysteries of God, therefore I make a record of my proceedings in my days. Yea, I make a record in the language of my father, which consists of the learning of the Jews and the language of the Egyptians. And I know that the record which I make is true; and I make it with mine own hand; and I make it according to my knowledge. For it came to pass in the commencement of the first year of the reign of Zedekiah, king of Judah, (my father, Lehi, having dwelt at Jerusalem in all his days); and in that same year there came many prophets, prophesying unto the people that they must repent, or the great city Jerusalem must be destroyed.

Mosiah 1:2-6 And it came to pass that he had three sons; and he called their names Mosiah, and Helorum, and Helaman. And he caused that they should be taught in all the language of his fathers, that thereby they might. . . know concerning the prophecies which had been spoken by the mouths of their fathers, which were delivered them by the hand of the Lord. And he also taught them concerning the records . . were it not for these plates . . . we must have suffered in ignorance . . . not knowing the mysteries of God. For it were not possible that our father, Lehi, could have . . . taught them to his children, except it were for the help of these plates; for he having been taught in the language of the Egyptians therefore he could read these engravings, and teach them to his children, that thereby they could teach them to their children that... we might read and understand of his mysteries . . . O my sons, I would that ye should remember that these sayings are true, and also that these records are true. And behold, also the plates of Nephi, which contain the records and the sayings of our fathers from the time they left Jerusalem until now, and they are true.