Back in Old Testament times, many men had multiple wives – every one of these marriages resulted in grief and heartache. Multiple wives were allowed by God, though He never recommended it.  God, also, gave the Israelites laws to reduce their problems when they chose to practice polygamy, though He did not forbid this practice. A couple of examples are:

* He did not allow a man to marry the sister of his wife while his wife was still alive (Leviticus 18:18)

* He did not allow the son of the favored wife to take the role of firstborn if the unloved wife’s son was born first (Deuteronomy 21:15-17)

Kings were specifically told not to have many wives (Deuteronomy 17:15-17). This was for the very specific reason that many wives could turn a king’s heart away from the Lord. King Solomon disobeyed this rule and experienced severe consequences (1 Kings 11:4-8). So, why did Solomon marry all of these women (700 wives and 300 concubines)? 1 Kings 11:3 tells us these wives were princesses – the daughters of other kings. By being married to their daughters, peace was maintained between their nations. No King was going to attack the country where his daughter was living. Solomon’s reign was peaceful in earthly terms, but did turn his heart from the Lord, bringing far worse difficulties on himself and the nation of Israel. In fact, at the end of his life, Solomon realized his mistake and concluded, “The end of the matter; all has been heard. Fear God and keep his commandments, for this is the whole duty of man.”

While God did allow multiple wives back in Old Testament times, His plan from the beginning was for there to be just one husband and one wife. This makes a beautiful picture of Christ and his church, as the Apostle Paul explains in Ephesians 5:22-33. Paul also quotes from Genesis 2:24 saying, “For this cause a man shall leave his father and mother and shall cleave to his wife; and the two shall become one flesh.”

Additional Resource: 
Christian Questions Podcast Episode #1241: “Is It a Sin if I …? (Part II)”
Discussing sex and sin-related questions using biblical principles
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