What does Mark 10:11 mean?

The Pharisees are trying to use Deuteronomy 24:1–4 to trick Jesus. They hope He will either admit that God allows divorce, or condemn divorce and remarriage and risk the wrath of Herod Antipas, as John the Baptist did (Mark 6:17–18). Jesus counters that, yes, the Mosaic law allows divorce for indecency in the wife. But if a man divorces his wife for anything less than her adultery (Matthew 5:32; Luke 16:18) and then marries another, he is committing adultery. The scribes teach that if a man so much as found another woman he was more attracted to, he could divorce his wife and marry the new woman. Jesus explains that is not the point of the law.

When Jesus brings the conversation from grounds for divorce to adultery, He swings the subject from scribal tradition to one of the Ten Commandments (Exodus 20:14). The situation is more serious than the Pharisees—and disciples—let themselves believe. It hadn't occurred to them that a man could commit adultery against his wife. That comment only seems strange to modern ears because of the teachings of Christ. In the Mosaic law, a man could only commit adultery against the husband of the woman he slept with, if she was married (Leviticus 20:10). In simple terms, per the Jewish worldview, only a man could be the victim of adultery. Jesus, as He does so often, raises the status of women to fully human (1 Corinthians 7:4).

As to remarriage and adultery, Paul affirms that if a couple divorce, they should either remarry each other or remain unmarried (1 Corinthians 7:11). However, if either does remarry after divorcing for a cause other than infidelity or abandonment (1 Corinthians 7:15), the act of getting remarried is the sin of adultery, not the state of being remarried. A remarried person should not divorce their current spouse (1 Corinthians 7:20). Whether this restricts a person's opportunity for ministry depends on the local church's interpretation of 1 Timothy 3:2, 12, and 5:9, and Titus 1:5–6.