These verses contain some of the most unsettling and radical ideas in the entire Sermon on the Mount. Jesus takes Old Testament commandments about murder, adultery, divorce, oath-keeping, and revenge and takes them one step further. It is not enough, according to Jesus, to simply keep the letter of the law. That is just the starting point. To truly fulfill the law, we need to pay attention to what is in our hearts, our motivations, and be governed by a spirit of love.