Why did the Bible allow men to have more than one wife?

The Bible describes many Old Testament figures—Abraham, Jacob, David, Solomon—having more than one wife, but notice the difference between the Bible describing something and the Bible approving of it.

Genesis actually sets one man and one woman as the creation pattern from the start: "a man leaves his father and mother and bonds with his wife, and they become one flesh" (Genesis 2:24)—singular wife, not multiple. Jesus later points back to this exact verse as God's real design for marriage (Matthew 19:4–6).

The Old Testament regulates having more than one wife without ever commanding it, and its stories consistently show the practice causing real pain—jealousy, favoritism, and family breakdown, from Abraham's household to Jacob's to Solomon's.

By the New Testament, church leaders are explicitly expected to be "husband of one wife" (1 Timothy 3:2), and the whole New Testament assumes marriage as one man and one woman—the pattern most Christian traditions see as God's actual design all along.