Midway through his now-famous letter from the city jail in Birmingham, Alabama, the Rev. Dr. Martin Luther King, Jr. defended the ongoing protest marches against segregation by quoting the prophet Amos: "Let justice roll down like waters and righteousness like an ever-flowing stream." At another point in the letter, he referred to the passage in the Book of Daniel in which Shadrach, Meshach and Abednego, under threat of death, refuse to bow before the gods of their Babylonian conquerors. King meant his letter primarily to chastise the moderate clergymen of Birmingham, most of them Christian, who considered the movement's direct action too radical. And in doing so, he cited many religious figures in the Christian sphere, from Jesus and St. Thomas to Reinhold Niebuhr and Paul Tillich. Even so, then and now, King's words carried an unexpected, unintended rebuke for Jews committed to social justice. One of the whopping paradoxes of the civil rights movement was that the Jews who comprised a disproportionate share of white activists and volunteers were largely ignorant of the theological roots of their idealism. With some rare rabbinic exceptions like Abraham Joshua Heschel and Jack Rothschild, they had to learn their own Bible from the black Christians in the campaign. The divide between religious knowledge and social action persists in American Jewish life. In the parts of the Jewish spectrum with the strongest involvement in tikkun olam, particularly among the secular and unaffiliated, there is the least awareness of the Judaic foundations of that concept. (In fact, there is often an antipathy to religion itself as mere superstition.) In the parts with the deepest knowledge of text and tradition, particularly the Orthodox sector, a formidable apparatus of charities exists almost entirely to serve internal needs. ONE OF the reasons that American Jewish World Service under the leadership of Ruth Messinger has become such a phenomenon, I am convinced, is that it has overtly connected activism (in the form of Peace Corps-like projects in developing nations) to a disciplined, ongoing study of Jewish texts. It has taken its young volunteers past that inchoate, uninformed sense that there's something sort of Jewish about doing social justice. Occupying the unstable center of American Jewish life, a place defined more by what it isn't than what it is, the Conservative movement has struggled over the years to reconcile contemporary Jewish political impulses with traditional Judaic religious injunctions. Now at least a partial reconciliation is at hand, and it is one with relevance and resonance far beyond the Conservative movement alone. A rabbi in suburban Minneapolis-St. Paul, Morris Allen, has led the movement to create a new form of kosher certification, which he calls a hechsher tzedek. As the name implies, this certification would reflect a commitment to justice on behalf of kosher food companies rather than solely their adherence to the laws of kashrut in food preparation. Put another way, the hechsher tzedek puts the treatment of human beings at least on a par with the treatment of an animal. Many of the humans in question are Latino immigrants who have filled the labor vacuum in slaughterhouses across the United States and been the victims of both exploitative bosses and nativist bigots. The plant that first caught Rabbi Allen's attention several years ago is Agriprocessors in eastern Iowa. The facility, which is owned by a Lubavitcher family and produces the most kosher meat of any plant in the United States, has been controversial for nearly a decade. First the journalist and author Stephen Bloom, in his book Postville, depicted the Hassidic owners and managers not as the rescuers of a depleted local economy but as harsh, rigid outsiders. A series of articles by Nathaniel Popper in the Forward detailed the below-market wages and dangerous conditions in the plant. While Agriprocessors inspired the hechsher tzedek, if "inspired" is the word, the certification plan would cover the entire $11.5-billion-a-year industry. To earn the hechsher tzedek, an employer, meaning in most cases a large corporation, would have to pay wages consistent with regional rates, provide employees with health care and vacation benefits, and offer safety training to workers in a language they understand, among other requirements. The hechsher tzedek would augment rather than replace existing certifications, most of them issued by Orthodox va'ads. AT THIS point, the plan is moving gradually yet steadily closer to becoming reality. The Rabbinical Assembly, the organization of Conservative rabbis, has formally endorsed it. The Nathan Cummings Foundation, a respected institution in Jewish philanthropy, has given a $50,000 grant. At its biennial meeting this week, the United Synagogue of Conservative Judaism, the movement's congregational arm, is taking up a detailed paper citing the textual bases for the hechsher tzedek in the Tanakh, the Talmud and Shulhan Aruch. Those citations, at least as I read them as a lay person, make a sensible, unforced link between Judaism and this particular form of social justice. As a theological treatise for labor rights, it reminds me of the papal encyclical Rerum Novarum, a cornerstone of trade unionism in the 20th-century West. It helps, too, that Rabbi Allen was a prominent advocate for increasing kosher observance in Conservative circles before taking up this cause. No one can accuse him of discovering kashrut just in time to change the rules. I have a hard time imagining that more Jews would become kosher as a result of hechsher tzedek, but the size of the kosher food market suggests that many Jewish consumers, while indifferent to most of the dietary laws, still buy kosher meat for reasons of sentiment, solidarity or perceived quality. How many of them naively think that glatt - a concept, indeed a social construction, that barely existed in the United States before World War II - connotes some higher kosher status, when it's more like higher price? So just as idealism and commerce have fruitfully commingled in the booming sales of hybrid cars and the campus protests against sweatshop labor, this kind of cross-pollination could find its Jewish expression in hechsher tzedek. It could provide a living object lesson in the relevance of tradition to modernity, and of the inextricable interplay of Judaism and what we like to think of as a Jewish set of values. And, for once, we wouldn't need a Talmud Torah lesson from a Baptist preacher to get the point.