In 1 Nephi 7:1 we find that the Lord spake unto Lehi, "saying that it was not meet for him, Lehi, that he should take his family into the wilderness alone; but that his sons should take daughters to wife, that they might raise up seed unto the Lord in the land of promise." According to Donna Nielsen, a knowledge of the biblical marriage imagery can greatly enrich our understanding of how God relates to us through covenants. Jewish tradition and law dictated that marriage was not an option. Anciently the Jews believed that a man would not receive the highest blessings that life offered without a woman by his side. Accordingly, the word for "salvation" in Hebrew (jeshu-ah) is a feminine term. The Jews believed that marriage was an important element of salvation. Celibacy was not considered to be a virtue. There is not a word in biblical Hebrew for "bachelor." Even the modern Hebrew word for bachelor, ravak, comes from a root word meaning "empty." [Donna B. Nielsen, Beloved Bridegroom: Finding Christ in Ancient Jewish Marriage and Family Customs, pp. 2-3]
“The Lord Spake That Lehi's Sons Should Take Daughters to Wife That They Might Raise Up Seed Unto the Lord”
According to John Welch, Lehi was a real person, who lived in a real world. It is a testimony to him to see how aptly his words fit into the ancient legal setting as we understand it. An important power retained by the father in ancient Israel was controlling whom his sons and daughters would marry. The parents "very often chose a wife for their son, although sometimes the son himself contracted the marriage" (Falk 162, citing Gen. 26:34; 37:46; Judges 14:2, 7). It was the duty of each person to take and be taken in marriage, and it was the obligation of parents to see that their children were married (DJ 11:1049; Clark 128). The importance of this parental duty is reflected in the prophet Jeremiah's command to those leaving Jerusalem shortly after Lehi's departure to "take ye wives, and beget sons and daughters; and take wives for your sons, and give your daughters to husbands" (Jeremiah 29:6; emphasis added).
Lehi acted in accordance with these general principles. He largely controlled whom his sons and daughters married. Through him came the commandments of the Lord that "his sons should take daughters to wife" and that they should return to Jerusalem to get Ishmael and his family for this very purpose (1 Nephi 7;1-2). As far as we know, no objections were raised by Lehi's sons, nor were their preferences consulted. Furthermore, it is said that by seeing his sons married, Lehi "fulfilled all of the commandments of the Lord which had been given unto him" (1 Nephi 16:8). Thus, Lehi's own obedience to the Lord included the duty of seeing that his sons were married. [John W. Welch, "Lehi's Last Will and Testament: A Legal Approach," in The Book of Mormon: Second Nephi, The Doctrinal Structure, pp. 62, 66-67]
“That They Might Raise Up Seed Unto the Lord in the Land of Promise”
The Lord commanded Lehi that "his sons should take daughters to wife, that they might raise up seed unto the Lord in the land of promise" (1 Nephi 7:1). According to Reynolds and Sjodahl, the first divine commandment to men created in God's image, was: "Be fruitful, and multiply and replenish the earth, and subdue it" (Genesis 1:28). In order to enable Adam to keep this divine law, God formed a woman of a "rib" taken from the side of Adam, wherefore he, on seeing this new, glorious creation, said, "This is now bone of my bones and flesh of my flesh: She shall be called woman, because she was taken out of man." The Creator added to this: "Therefore shall a man leave his father and mother, and shall cleave unto his wife; and they shall be one flesh." (Genesis 2:22-24; 19:4-5) The commandment to replenish the earth has not been canceled; it will be in force until the entire earth is filled with the children of God. . . .
The word which in the story of the creation of man is translated "rib," (Hebrew zelah) occurs 38 times in the Old Testament. Nowhere, except in that account, is it rendered "rib." In a number of passages it is translated "side." (Exodus 25:12,14; 26:20; 27:7; 36:25,31; 37:35; 38:7) In 2 Samuel 16:13 it is rendered, "hillside." And in Ezekiel 41 it occurs ten times and is rendered, "side chambers." Why the translators of Genesis should have preferred "rib" to "side" is a mystery. "Chamber" would, in my [Reynolds' and Sjodahl's] opinion or judgment be preferable. The side chambers of the temple were used for sacred purposes. In some of them the sacred utensils and the vast treasures of the sanctuary were, no doubt, stored. But the body of Adam was a temple of God, with its side chambers, as well as main chambers, in which the main springs of life were stored. From these chambers it pleased God to draw his material for the second sacred structure, to be joined to the first. And so Adam, who was perfectly conscious of what the Lord had done during his sleep, exclaimed, as soon as he saw the new creation, "This is now bone of my bones, and flesh of my flesh." [George Reynolds and Janne M. Sjodahl, Commentary on the Book of Mormon, Vol. 1, pp. 55,59]