Though we citizens of the new millennium like to think we have rights, we have much to gain from the realization that what we really have are gifts. To be sure, those of us privileged to live in enlightened democracies are granted an assortment of civil rights by our governments. But those rights, indeed those governments, are not owed us. The vast majority of human beings over the course of history knew nothing of such gifts, and neither, unfortunately, do all too many people today. That nothing we take for granted deserves to be is a deeply Jewish idea. The word Jew hints as much, derived as it is from the name Judah, which Jewish tradition roots in Judah's mother Leah's declaration that she was the beneficiary of "more than my share." The understanding that nothing is coming to us is what Jewish tradition calls hakarat hatov, or "acknowledgment of the good." It is a concept much eroded in our times, a casualty of contemporary society's wealth, comfort and culture of rights. We fully expect the freedoms we enjoy, virtually demand shelter, education, a job, health care - for that matter, health. The downside of our insensitivity to hakarat hatov is that when the roof is suddenly removed from over our heads or we unexpectedly find a pink slip instead of a paycheck we feel angry and betrayed. Disappointment would be understandable, of course (though one talmudic personality welcomed every turn of fortune, no matter how depressing, with the conviction "This too is for the good!"). But angry? Anger over circumstance can only take root when the ground has been prepared for it by the notion of illusory "rights" - when gifts have been taken for granted. We living organisms are frail creatures. At any given moment our lives depend on thousands of genetically programmed, incredibly complex biological processes. I remember when, as a younger man and avid motorcyclist, I first realized that all that stood between my skin and the 60-mile-an-hour concrete sandpaper whizzing by below was a flimsy-looking cotter pin, not much thicker than a heavy-duty paper clip. It alone prevented my Honda's rear wheel from going off to explore the world on its own. That feeling is surely familiar to anyone who has ever been seriously ill. The realization that the presence or absence of a particular blood chemical or protein or electrolyte can make all the difference between health and sickness - or life and death - is a potent eye-opener. And it should yield an incomparable sense of gratitude when everything works as it should, when we are granted the amazing gift - not right - of health. A YOUNG person once asked a rabbi why the Creator bothered to create so immense a universe when astronomers have only fairly recently become aware of the extent of its vastness. He replied that only recently has man needed to see the vast expanses of space - for modernity has infected us with a scientific hubris, a sense of omniscience. The sight of distant nebulae and the thought of "thousands of light years," he explained, are precisely what modern man needs - to afford him the same feeling of awe that a simple, unaided gaze at the night sky once easily and effectively provided. Today's increasingly evident auto-immune diseases might be the biological side of the same coin. Medicine has become so sophisticated that we feel doctors or drugs can do almost anything, as if we truly control our own healths. Such self-assurance takes a considerable toll on our awareness of the miraculous gift of our biology. It dulls our sensitivity to the presence of the divine in our physical lives. We come perilously close to worshiping our achievements rather than our Creator. Enter diseases that do one simple but horrifically significant thing: ravage the immune system. In other words, they prevent a gift from doing what it regularly and naturally - if miraculously - does. By crippling the body's complex natural ability to ward off myriad unseen but dangerous invaders - routinely repelled by healthy immune systems day in and day out - they wreak terrible havoc. The diseases that result are tragedies, but priceless lessons too. They remind us that the workings of our bodies are a wondrous gift, and that we owe boundless gratitude to their Source. Jewish tradition prescribes the recitation of blessings on many occasions: the performance of a commandment, the partaking of food or drink, the enjoyment of a fragrance. A Jewish blessing, however, that has raised many an eyebrow is the one recited by observant Jews after leaving the bathroom. It expresses gratitude for God's having "formed human beings with wisdom," for the gift of our functioning bodies. Truly a blessing for our age. The writer is director of public affairs for Agudath Israel of America.