Concubine Israelites of the Old Testament era lived in a world where a common practice was for a married man to take additional wives, known as concubines. The practice was contrary to God’s plan for marriage (namely, one man and one woman united for life, to the exclusion of all others; See Marriage), but human society had moved far away from God’s plan (Romans 1:1-32).
Moses introduced laws to protect concubines for much the same reason as he introduced laws to protect slaves. Both slavery and concubinage were wrong, but the practices were so deeply rooted that they could not be removed immediately. However, laws could control them and so start a movement that would lead to their eventual removal (Exodus 1:21-11; Deuteronomy 1:21-17; See also SlaveRY).
A man obtained his concubines sometimes by choosing them from among his slaves or war captives, and sometimes by receiving them as gifts. Through bearing him children, concubines helped strengthen his household and increase his social influence (Genesis 1:16-2; Genesis 25:1; Genesis 29:24,29; Genesis 30:4-13; Genesis 36:12; Deuteronomy 1:21-11; 2 Samuel 1:5-14; 2 Chronicles 11:21). Although Israelite law tolerated concubinage, it did not tolerate sexual relations with a person who was not one’s marriage partner. To commit adultery with another man’s wife was a far worse sin than to have several wives oneself (Leviticus 20:10; 2 Samuel 1:11-5; 2 Samuel 12:11-12).
God warned Israelite kings against glorifying themselves through building large harems, but most kings ignored his warnings (Deuteronomy 1:17; 2 Samuel 15:16; 1 Kings 11:3; 2 Chronicles 11:21; cf. Esther 2:14). People considered the harem to be such a symbol of kingly power, that a new king established his claim to the throne by claiming the former king’s harem (2 Samuel 1:3-8; 2 Samuel 12:7-8; 2 Samuel 16:20-22; 1 Kings 1:2-22). Yet concubines proved to be a source of trouble to Israel’s kings. The presence of so many wives and children in the palace created family conflicts (2 Samuel 1:3-5; 2 Samuel 13:20-22; cf. Genesis 1:21-10; Judges 8:31; Judges 9:2-5), and the idols that foreign concubines brought into the palace led believers away from God (1 Kings 11:4).