What does Matthew 5:43 mean?

Matthew 5:43 begins one of the six "antitheses" in Jesus's Sermon on the Mount, where he quotes a common teaching of his day and then deepens or corrects it. The verse itself is a setup line: Jesus tells his listeners that they have heard it said, "You shall love your neighbor and hate your enemy." He is not yet giving his own teaching here—that comes in verse 44, "But I tell you, love your enemies"—but rather naming the popular understanding he is about to challenge. Read in isolation, this verse simply states what people commonly believed and practiced regarding love and hatred toward others.

The first half of the quotation, "love your neighbor," comes directly from Leviticus 19:18, part of the Mosaic law. The second half, "hate your enemy," is not found anywhere in the Old Testament as a direct command. Instead, it reflects a popular extension or common assumption that many teachers and ordinary people had drawn from the law—since God's people were told to love their neighbor (often understood narrowly as fellow Israelites or those within one's community), it seemed to follow logically that hostility toward outsiders, enemies, or those excluded from that circle of "neighbor" was permitted or even expected. Jesus, speaking to a Jewish audience in Galilee, is addressing this cultural and religious assumption directly. He often uses the phrase "you have heard that it was said" to introduce not necessarily what Moses commanded, but how that command had come to be popularly interpreted, sometimes narrowed or distorted over