Too many of us who call ourselves Christians — especially in a wealthy country like ours — live our religious beliefs as if they were pious clichés. We use our faith to comfort ourselves when we feel sad, or when we suffer. Many of us never really carry Christ beyond that. We're embarrassed to share Him with others. We're afraid to apply His teachings to our racial attitudes, or our economy, or our politics. And frankly, that suits modern society very well, because when our faith remains private, it has no public consequences — and the business and callousness and injustice of the world can go on as usual.

The trouble with such faith is this: It's a form of lying. It's hypocrisy. And Dr. King understood that very well. I think Dr. King saw clearly and prophetically that the greatest enemy of God in every age doesn't come in the shape of the world or the flesh or the devil. It's the lukewarm faith of God's people. If we want to know why the world isn't a better place, we only need to look in the mirror.

There's an old saying, "If you want to know a man, don't listen to what he says; watch what he does." Christians have always known this from the Epistle of James which tells us to "be doers of the word and not hearers only" (1:22), because "faith by itself, if it has no works, is dead" (2:17). God didn't make us to be "good enough" human beings. He made us to be saints. He made us for greatness and heroism. Every human heart, Christian or not, instinctively knows that. St. Irenaeus once wrote that, "the glory of God is man fully alive." God calls each of us to transform the world, and if we don't live the way God intended us to live, the world will remain as it is — a place of conflict and prejudice and violence.

The glory of God is the human person, fully alive. Martin Luther King Jr. was a man fully alive and free, because he loved better than his enemies could ever hate. It's easy to say, "love your enemies." It's a very different thing to actually do it, or even try to do it. Dr. King once said, "If you want to change people, you have to love them; and they need to know you love them." I've never forgotten those words. Dr. King loved well, and by the power of that love, he helped to change the heart of a nation. He returned persecution with forgiveness, and by the power of that forgiveness, he showed that real strength and real justice come from love, not violence.

In his "Letter from a Birmingham Jail," Dr. King wrote: "The question is not whether we will be extremist, but what kind of extremist we will be. Will we be extremists for hate, or extremists for love? Will we be extremists for the preservation of injustice — or will we be extremists for the cause of justice?" Dr. King answered those questions by the example of his life. He chose love. He chose justice. And the witness he left us invites every one of us, Christian and non-Christian alike, to do the same.

Don't lie when you pray. We need to live honestly. We need to act on the convictions we say we believe — racial equality, economic justice, the sanctity of the human person. The biggest lie of the last 100 years is that individuals can't make a difference; that our problems are too complicated for little people like you and me to do anything about them.

Dr. King proved that God can use us to do anything — anything, even touch the conscience of the greatest power on earth — if a person fights for the truth in a spirit of love. That's what the life of Martin Luther King Jr. means. That's what discipleship under Jesus Christ means. That's a lesson we all need to learn.