What does Matthew 10:35 mean?

Many Jewish people believed the Messiah's arrival would immediately bring a new age of peace and prosperity to Israel. Jesus, though, never taught this. Instead, He warned that His arrival on earth would bring a new era of division between Israelites. Later, belief in Him would become a dividing line between Gentiles, as well. In the prior verse, He referred to the effect of His ministry as bringing a "sword." The specific Greek term He used is the same as found in Hebrews 4:12: a reference to a razor-sharp blade used to trim meat.

He now tells His disciples He has come to set fathers and sons against each other. The same will be true for mothers and daughters, as well as mothers-in-law and their daughters-in-law. Those who do not believe in Jesus will turn on those in their families who do (1 Peter 4:3–4; John 15:18–21).

This language would have been very familiar to Israelites who had grown up hearing the Old Testament Scriptures. Micah wrote about a time in Israel's history, under the rule of King Ahaz, when Israelites distrusted and turned on each other, even those in their own families (Micah 7:6). Jesus now reveals that the same will happen again in response to the coming of the Messiah, Himself. This may have begun during Jesus' ministry on earth, but it took root and expanded after His death, resurrection, and return to heaven.