Among all the religious symbols in the world none is more universal than the cross. You see crosses everywhere, on walls, on hillsides, in churches, in houses, in bedrooms, on chains around peoples’ necks, on rings, on ear-rings, on old people, on young people, on believers, and on people who aren’t sure in what they believe. Not everyone can explain what the cross means or why they choose to wear one, but most everyone has an inchoate sense that it is a symbol, perhaps the ultimate symbol, for depth, love, fidelity, and faith.

And the cross is exactly that, the ultimate symbol of depth, love, fidelity, and faith. Rene Girard, an anthropologist, once commented that “the cross of Jesus is the single most revolutionary moral event in all of history.” The world measures time by it. We are in the year 2007 (roughly) since Jesus died on a cross and ever-increasing numbers of people began to organize their lives around its significance.

What is so morally revolutionary in the cross?

Precisely because it such a deep mystery, the cross is not easy to grasp intellectually. The deeper things in life, love, fidelity, morality, and faith are not mathematics, but mysteries whose unfathomable depths always leave room for more still to be understood. We never quite arrive at an adequate understanding of them.

But that doesn’t mean that we don’t know them. Knowing is different than understanding and we intuit a lot more than we can intellectually imagine or express.

For example, TIME magazine did a cover story some years ago on the meaning of the cross and interviewed a large number of people asking what the cross of Jesus meant to them. One woman admitted that she couldn’t really explain what the cross of Jesus meant to her, but stated that she had a sense of its meaning: When she was young girl, her mother was murdered by a jealous boyfriend. When she saw the blood-soaked mattress and her mother’s bloody hand-print on the wall, she realized that she had to find a connection between her mother’s story (and her blood on that mattress) and Jesus’ story (and his blood on the cross.) Sometimes the heart intuits where the head needs to go.

Beyond this gut-knowledge, what can we intellectually grasp about the meaning of the cross? What is its revolutionary moral character?

Theologians, classically, have tried to come to grips with this mystery by dividing the meaning of the cross (and of Jesus’ death) into two parts: First, the cross gives us our deepest understanding of the nature of God. Second, the cross is redemptive, it saves us. All Christians believe that somehow we are washed clean in the blood of Jesus, the Lamb of God.

Neither of these concepts is easy to explain, though theologians do better with the first, the cross as revelation, than with the second, the cross as redemptive. But both concepts, even to the limited extent that we can intellectually understand them, are thoroughly morally revolutionary.

Christianity is 2000 years old, but it took us nearly 1900 years to fully grasp the fact that slavery is wrong, that it goes against heart of Jesus’ teaching. The same can be said about the equality of women. Much of what Jesus revealed to us is like a time-released medicine capsule. Throughout the centuries, slowly, gradually, incrementally, Jesus’ message is dissolving more deeply into our consciousness.

And this is particularly true about our understanding of the cross and what it teaches. For example: There have been popes for 2000 years, beginning with Peter, but it was only the last Pope, John Paul II, in our own generation, who stood up and said with clarity that capital punishment is wrong (independent of any arguments about whether or not it is a deterrent, brings closure to the victims’ families or not, or can be argued in terms of justice) Capital punishment is wrong because it goes against the heart of the gospel as revealed in the cross, namely, that we should forgive murderers, not kill them.

That is just one of the morally revolutionary features inside of the cross. There are countless more. Rene Girard, speaking as an anthropologist, puts it one way when he says that the cross is the most revolutionary moral event in the history of the planet. Mark, the Evangelist, speaking as a disciple of Jesus, puts it another way: For him, the cross of Jesus is the deep secret to everything.

In Mark’s gospel, to the extent that we understand the cross of Jesus, we grasp life’s deepest secret. And the reverse is just as true: To the extent that we don’t grasp the meaning of the cross, we miss the key that opens up life’s deepest secrets. When we don’t grasp the cross, life deep mysteries become a riddle.

Both Mark and Rene Girard are right: The cross of Jesus contains life’s deepest moral secret, but, as Rumi says, we live with a secret we sometimes know, and then not.