“I didn’t come to bring peace, but a sword.” People are so quick to say, “Oh, Jesus never judged anybody.” What they mean is we have to accept everyone, and never say anything is wrong or that anyone is doing wrong. They obviously haven’t read this part. Fire was a symbol of judgment, and Jesus said, “I’ve come to bring fire on the earth. How I wish it was already lit.” Ouch. It’s not that Jesus is anxious to fry people in judgment. What he’s saying is that he has a deep desire that all this part was done with (the conflicts, the altercations with the Pharisees, and the cross) so there can be eternal rest in heaven.
Didn’t come to bring peace? John 14.27 says exactly that—that he came to bring peace. Yes, in many senses Jesus came to bring peace to individuals, by saving them, freeing them from the slavery of sin, breaking down barrier walls between people, and reconciling people to God. But in another sense, the person of Jesus brings conflicts between people, as many people mock and treat him with derision, while others worship. People fight over Jesus and over faith, and he doesn’t gloss over that part.
But that’s not really the point. The point is that sin will be judged now, just as it was in ancient Israel. Sin causes deterioration of families, relationships, and societies. Jesus has come to heal, restore, and reconcile, but many don’t accept it, and that in itself creates more problems.
But then when he says “they’ll be divided, father against son,” etc., that’s actually a quote from Micah 7.6, a passage about the sin that caused that exile, and the forgiveness that restores people, reconciling them to God and to each other. So what he’s really talking about, though it isn’t clear on the surface, is his whole mission in coming to earth, especially the cross. In the Micah passage, things had gotten so bad in the country, because they had deserted the Lord, that families were breaking up and the whole society was crumbling. But Micah says in 7.7: “But as for me, I watch in hope for the LORD, I wait for God my Savior; my God will hear me.”
Christ has come to knit families together, even all of humankind. And so people are bonded to each other through Christ. Christians should be at the forefront of healing fractured families and of reconciling people to each other. But equally Jesus’ presence can create disruption. As in ancient Israel, the prophets of the Lord got killed. When Jesus came, people lined up for him, and against him. Many families were brought together in Him, and I am hard-pressed to come up with a single Scriptural example of a family that was torn apart by faith. God created families to work, not to fall apart. It was not His desire that some families were torn apart, but you can never say never. Sin being what it is, it happens. There will always be a tension between darkness and light (2 Cor. 6.14).