A principal reason why the civil rights movement of the 1950s and 1960s was so successful, both morally and practically, was that it was led largely by people with a strong religious sensibility. The most notable of these leaders was, of course, Martin Luther King. To appreciate the subtle play between King's religious commitment and his practical work, I would draw your attention to two texts -- namely, his "Letter from the Birmingham City Jail" and his "I Have a Dream" speech, both from 1963.

While imprisoned in Birmingham for leading a nonviolent protest, King responded to certain of his fellow Christian ministers who had criticized him for going too fast, expecting social change to happen overnight. The Baptist minister answered his critics in a perhaps surprising manner, invoking the aid of a medieval Catholic theologian. King drew their attention to the reflections of St. Thomas Aquinas on law, specifically Thomas' theory that positive law finds its justification in relation to the natural law, which finds its justification in relation to the eternal law. Aquinas means that what makes a practical, everyday law righteous is that it somehow gives expression to the principles of the moral law, which in turn are reflective of God's own mind. Therefore, King concluded, unjust positive laws, such as the Jim Crow regulations that he was contesting, are not just bad laws; they are immoral and finally offensive to God.

Here is King's own language: "One may well ask: 'How can you advocate breaking some laws and obeying others?' The answer lies in the fact that there are two types of laws: just and unjust. I would be the first to advocate obeying just laws. One has not only a legal but a moral responsibility to obey just laws." But then King contrasts this with obedience to an unjust law: "Conversely, one has a moral responsibility to disobey unjust laws. I would agree with St. Augustine that 'an unjust law is no law at all.'" And in clarifying the difference, he turns to Aquinas: "Now, what is the difference between the two? How does one determine whether a law is just or unjust? A just law is a manmade code that squares with the moral law or the law of God. An unjust law is a code that is out of harmony with the moral law. To put it in the terms of St. Thomas Aquinas: An unjust law is a human law that is not rooted in eternal law and natural law." This is not pious boilerplate; rather, it reveals what gave King's movement its justification and purpose.

The very same dynamic was on display six months later, when King addressed the throng who had gathered at the Lincoln Memorial for the March on Washington. He was not giving a sermon. He was making a political speech, advocating in the public place for social change. But attend to some of the language that he used: "I have a dream that one day every valley shall be exalted, and every hill and mountain shall be made low, the rough places will be made plain, and the crooked places will be made straight; 'and the glory of the Lord shall be revealed and all flesh shall see it together.'" He was directly relating the social revolution he was advocating to the mystical vision of the prophet Isaiah. And listen to the magnificent conclusion of the address in which he artfully blends the lyrics of an American patriotic song to the lyrics of a song he and his family sang in church: "And when this happens, and when we allow freedom ring, when we let it ring from every village and every hamlet, from every state and every city, we will be able to speed up that day when all of God's children, black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual: Free at last! Free at last! Thank God Almighty, we are free at last!" Once again, on King's reading, the political nests within the moral, which nests within the sacred.

Martin Luther King derived from his religious heritage not only the metaphysics that informed his social activism, but also the nonviolent method that he employed. What Jesus reveals in the rhetoric of the Sermon on the Mount ("Love your enemies"; "Bless those who curse you, pray for those who maltreat you"; "If someone one strikes you on the right cheek, turn and give him the other"; etc.) and even more strikingly in his word of forgiveness from the cross is that God's way is the way of peace, nonviolence, and compassion. As a Christian, King knew in his bones that reacting to oppression with violence would only exacerbate the tensions within society. He sums up this principle in one of his best-known sermons: "Returning hate for hate multiplies hate, adding deeper darkness to a night already devoid of stars. Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that."

Within the confines of this brief article, I cannot begin adequately to address the social upheaval occurring in our culture today. But I will say simply this: it is indisputably clear that there are severe moral deficits in our society that must be addressed, but the best way to do so is from within a moral and finally religious framework. May Martin Luther King's model of leadership in this regard be a lodestar.

- Bishop Robert Barron is the founder of the global ministry, Word on Fire, and is an Auxiliary Bishop in the Archdiocese of Los Angeles.