Matthew was an apostle, a gospel writer. But before he was Matthew, he was Levi: a Jew who worked for the Roman IRS. As long as Rome got its part, the tax collectors could take as much as they wanted. They got rich by making people poor.
One of the most difficult relationship questions is “What do we do with a Levi?” Your Levi is the person with whom you fundamentally disagree. You follow different value systems. Your Levi is your “opposite you.” What if your “opposite you” is your boss? Your parent or child?
How does God want us to respond to the Levis of the world? I wonder if the best answer might be found in: “Accept one another, then, just as Christ accepted you, in order to bring praise to God” (Romans 15:7). This is how happiness happens.