Today is Easter, the holiest day in the Christian calendar.

The feast commemorates the resurrection of Jesus Christ: Christianity's founding event. Easter's date is linked with that of Passover, which marks a central moment in the life of the Jewish people -- their liberation from slavery in Egypt.

In one sense, these two great holidays -- holy days -- should interest not only religious believers, but all Americans. They remind us that our Judeo-Christian heritage is the font of two principles at the heart of our national project: Liberty and equality.

America was founded on the belief that God is the source of both.

The political philosophy that inspired our nation's democratic revolution was very different from the Continental European philosophy that produced the French Revolution.

That bloody tradition grounded its political thinking in autonomous human reason. America's founders, on the other hand, looked "to the sovereignty of God as to the first principle of its organization," as the theologian John Courtney Murray has written.

Think of the Liberty Bell, emblazoned with an inscription from the book of Leviticus in the Old Testament, the Hebrew Bible: "Proclaim Liberty Throughout All the Land Unto All the Inhabitants Thereof."

Think of the Declaration of Independence: "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness."

Today, American democracy's Judeo-Christian roots are no longer well-understood or appreciated. In fact, we're accustomed to hear religious faith abused by influential voices intent on driving it to the margins of our public square.

The "cultivated despisers of religion" who sneer at faith generally dismiss it as irrational. And because it is irrational, they insist, it is of private interest only, and has nothing to contribute to public debates about law, morality or public policy.

But all human beings -- believers or atheists -- approach the world from the vantage point of faith. We all start with certain bedrock principles, or fundamental axioms, that can't be logically proven and that underpin all else that we believe.

In Judeo-Christianity, faith is seen in dialogue with reason. A fundamental Judeo-Christian axiom, for example, is that man is made in the image of God. This means he is a rational agent who can know right from wrong. Man's divine origin gives him a unique dignity and makes human life precious and holy.

Human beings' divine origin also makes them equal in the sight of God. And it fits them for freedom. Men and women are bearers of "unalienable," God-given rights that the state did not create so can never rightly take away.

A second Judeo-Christian axiom is that truth exists -- that there are truths built into the world and into us. These truths include principles of justice that ordinary people can discover through reason, and on the basis of which they can order their life together.

This human capacity is what makes democracy possible. Judeo-Christianity teaches that truth is accessible, not just to kings or scientific experts but to common people.

Today, our opinion-making elite have largely jettisoned the Judeo-Christian vision in favor of scientific materialism. This worldview's axiom -- its article of faith -- is that man is a cosmic accident, a product of blind physical processes.

Scientific materialism offers no philosophical basis for human dignity or human rights, for freedom or equality or limited government. It offers no reason that the wisest or mightiest -- the scientists or military men or beneficent social engineers -- should not rule the rest of us.

The left and much of our opinionmaking elite want to delegitimize and privatize religion for two reasons.

First, they don't like the idea of truth -- the idea that there is, in the nature of things, a blueprint for human flourishing. They don't like the notion of moral parameters that limit our actions on matters such as cloning, stem cell use, abortion or marriage. They believe that man can make himself: that there is no "floor" to the universe.

Second, our elite's fundamental political impulse is toward collectivism. They believe the state holds the solution to every problem, and that wise social engineers can be trusted to do what's best for the rest of us.

Religion is a threat to them, because it stands between the individual and the state. This is why totalitarian governments like the Soviet Union and Nazi Germany have always sought to stamp out or control religion.

Judeo-Christianity gives human beings a source of truth independent of the state, a higher law. It is a fundamental allegiance, a shaper of conscience and behavior. And in America, it is the source of human freedom.

Katherine Kersten is a senior fellow at the Center of the American Experiment. The views expressed here are her own.

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