What does Matthew 5:32 mean?

In the previous verse, Jesus described the standard teaching on divorce from the Jewish religious leaders. They allowed a man to give his wife a certificate of divorce for little or no reason, according to their interpretation of Deuteronomy 24:1–4. This "interpretation," as it turns out, left out not only much of the original wording but almost all the original purpose.

Jesus once again demonstrates God's true and original intent. In this case, God means for marriages to be for life. Rather than agreeing that marriages can or should be dissolved for petty reasons, Christ describes divorces motivated by something less than sexual immorality to be invalid. That's not to say this is the one and only reason of any kind that might justify a divorce. The primary point is that a man may not legitimately divorce his wife unless she violates the marriage through adultery or some other sexual immorality.

Because the divorce is invalid, the man is guilty of causing his wife to commit adultery when she remarries another man. In the same way, a man who marries a woman whose divorce was not for a valid reason also becomes guilty of adultery. From Jesus' view, false divorces—no matter how legal the religious leaders say they are—lead to more and more adultery. He was shockingly clear about the penalty for adultery and lust (Matthew 5:27–30).

Jesus' teaching here is not simply a reflection of some obscure, fussy rule. It's because God instituted marriage, and deeply values it for its own sake. Marriage is not only the fundamental relationship of every culture; it is meant to be a representation of Christ and the church (Genesis 2:24–25; Ephesians 5:25–33).