Jesus continually runs up against legalism. The synagogue leader wasn’t a total idiot, he was just doing his job. Probably, he was deeply concerned with reverence for the law. How does Jesus answer that? By reminding everyone of the value of people (“love your neighbor” had been around for a while too) and by showing what the Kingdom was like in illustrations. These parables use the image of very small things that produce something large, and indeed that was what happened with Jesus’ upside down Kingdom. It wasn’t happening from the top, those were the people who most often opposed him. It was a grassroots movement among those who had ears to hear.