Lehi was known to be wealthy, and some have speculated that he was a merchant who had frequent trade with Egyptian merchants. There was considerable cultural influence from Egypt in Jerusalem at this time and Lehi certainly knew the Egyptian language. Lehi was also well versed in the things of the Spirit. Therefore, Nephi was likely 'taught somewhat' in the secular and ecclesiastical learning of his father.
Hugh Nibley
"In the brief compass of Nephi's account, which is an abridgment of his father's own journal, whose type it imitates and continues ("1 Ne. 1:21 Nephi 1:2, "1 Ne. 1:15"1 Ne. 1:1615-16), we are given an amazing amount of information, both general and particular, regarding conditions in Lehi's day. From this it can be shown that Lehi has an excellent claim to being a thoroughly representative man of his time and place. First consider what the Book of Mormon says.
"Lehi was a man possessed of exceeding great wealth in the form of 'gold and silver, and all manner of riches' ("1 Ne. 3:161 Nephi 3:16; "1 Ne. 2:42:4). He had 'his own house at Jerusalem' ("1 Ne. 1:71 Nephi 1:7); yet he was accustomed to 'go forth' from the city from time to time ("1 Ne. 1:5"1 Ne. 1:6"1 Ne. 1:71 Nephi 1:5-7), and his paternal estate, the land of his inheritance, where the bulk of his fortune reposed, was some distance from the town ("1 Ne. 3:161 Nephi 3:16, "1 Ne. 3:2222; "1 Ne. 2:42:4). He came of an old, distinguished, and cultured family ("1 Ne. 5:14"1 Ne. 5:15"1 Ne. 5:161 Nephi 5:14-16)." (An Approach to the Book of Mormon, 3rd ed., p. 46.)