Jeff Jacoby

IN HIS "Letter from Birmingham Jail," written behind bars 50 years ago this week, Martin Luther King invokes God 15 times and mentions the words "Christ" or "Christian" 21 times. But he refers to "law" 41 times – more than both of them combined – and thereby hangs a lesson.

King was a Baptist minister and a scholar of theology. He had come to Birmingham with the Southern Christian Leadership Conference to head a nonviolent protest against the city's rigid segregation, and he wasn't the only pastor jailed for disregarding a ban on civil rights demonstrations. In an open letter to the local paper, a group of white religious leaders had publicly criticized the sit-ins, warning that such "extreme measures" – which were "led in part by outsiders" – were apt to "incite … hatred and violence." King read the ministers' statement after he was arrested. "Letter from Birmingham Jail" was his response.

Addressing himself to "My dear fellow clergymen," King explained that he had come to Birmingham "because injustice is here." Like Paul of Tarsus carrying the Christian gospel "to the far corners of the Greco-Roman world," he told them, "so am I compelled to carry the gospel of freedom beyond my own home town." He described the protesters' strategy of nonviolent confrontation as a long-delayed response to the refusal of Birmingham's leaders to soften their city's brutal and humiliating racial policies. "We had no alternative except to … present our very bodies as a means of laying our case before the conscience of the … community."

King admonished the clergymen who criticized him as extremist. Jesus too had been an extremist, he argued. So had the Prophet Amos and the English preacher John Bunyan. There were times when it was wrong not to go to extremes, and this was one of them. A great struggle to end the nightmare of American apartheid was underway, he wrote, and it made him weep to see "white churchmen stand on the sideline and mouth pious irrelevancies and sanctimonious trivialities."

Jeff Jacoby

Jeff Jacoby is an Op-Ed writer for the Boston Globe, a radio political commentator, and a contributing columnist for