The Lord commanded Lehi in a dream to send his sons back to Jerusalem for the plates of brass, then in the possession of an elder of the Jews named Laban. Lehi and his family did not have their own copy of the scriptures—roughly equivalent to our Old Testament—and Lehi did not want his children growing up without them, so the brothers had to go back.
Those plates were of such importance that the prophet was willing to risk all of his sons’ lives to obtain them. There’s a lesson on the significance of scripture study: the Lamanites continued without prophets and without scripture, and their society rapidly deteriorated.
We might ask, why did the Lord wait until they were more than two hundred miles away from home to command Lehi to get the plates? Could not arrangements have been made for them before the family left Jerusalem? One more test! The older brothers immediately protested. We may suppose that their foremost reason for not wanting to go was their fear of Laban; but there is no doubt that the distance and topography also had some bearing on their resistance. The Book of Mormon itself and most Book of Mormon commentaries say little, if anything, about the distance and terrain involved.
We have learned by walking it that the distance between Jerusalem and the Red Sea is two hundred miles. An agreeable pace for a group of people on camels would be between twenty and thirty miles a day. So the journey was a minimum of seven or eight days. Add to that the three days they traveled after reaching the Red Sea, and the figures are up to 260 to 290 miles in ten or eleven days. That is one direction only. The round trip that the Lord and father Lehi were asking of the four sons was more than 500 miles and at least three weeks through some of the most rugged terrain in the Near East. And they had no idea how they were going to obtain the plates. Having the advantage of “knowing the end from the beginning,” we are amazed to think ahead and realize that Lehi, soon after his sons returned from their first assignment, would command them to go back again. That is over a thousand miles and many weeks on those desolate tracts of land—and we have often looked down on Laman and Lemuel for being chronic complainers.