Many of the most devout followers of the most famous of all victims of capital punishment, the Nazarene who was crucified on the Calvary cross, took a long time to recognize that state-sponsored execution is an affront to their history and their faith. For close to 1,500 years, the Catholic Church taught that the state had a right to punish criminals “by means of penalties commensurate with the gravity of the crime, not excluding, in cases of extreme gravity, the death penalty.”

For centuries, that line in the Catechism of the Catholic Church was used by Catholic politicians–and others who sought a moral justification for their actions–to place a veneer of legitimacy on even the most cavalier executions of the young, the mentally handicapped and the innocent. Even as Pope John Paul II moved the church closer and closer to explicit opposition to the death penalty during his long tenure, the loophole in the Catechism remained.

Then, in 1997, Sister Helen Prejean, the American nun and death penalty abolitionist who authored the book Dead Man Walking, asked Pope John Paul II to close the loophole. Later that year, the Pope removed the reference to the death penalty from the Catechism and, when he visited the United States two years later, he denounced the death penalty as “cruel and unnecessary.” Referencing moves by countries around the world to ban capital punishment, the Pope declared in St. Louis that, “A sign of hope is the increasing recognition that the dignity of human life must never be taken away, even in the case of someone who has done great evil.”

So pointed and passionate was the Pope’s message on the issue that the then-governor of Missouri, Mel Carnahan, a Baptist and a supporter of capital punishment, commuted the sentence of a condemned man who was scheduled to be put to death by the state several weeks after the Papal visit.

It is to be expected that the death of a pope will be attended by hyperbole. And the passing on Saturday of John Paul II has proven to be no exception to the rule. The late pontiff has been credited with everything from defeating communism to healing the age-old rift between Catholics and Jews, just as he faces legitimate criticism for everything from undermining the fight against AIDS by preaching against the use of condoms to consigning the women of the church to second-class citizenship.

The legacy of a pope who served twenty-six years, five months and seventeen days–longer than all the popes in history, save St. Peter and the nineteenth-century pontiff Pius IX–will, of course, be subject to debate. Wise souls will for centuries ponder the accomplishments and the missteps of the man who began his earthly journey as a Polish boy named Karol Jozef Wojtyla and ended it as one of the most recognized and respected figures in the world.

But one aspect of this pope’s legacy is not up for debate. During John Paul II’s pontificate, the Catholic Church closed the loophole that had served as all-too-many justifications for the taking of the lives of prisoners of the state. New Orleans Archbishop Francis Schulte said the change opened up “a whole new area (of consideration) for many Catholics.” Sister Helen Prejean described it as a “Seismic shift” in church teaching. That shift had a profound influence on former Illinois Governor George Ryan, who declared the capital punishment system in Illinois “broken,” and commuted the sentences of all 167 inmates sitting on death row in Illinois jails in 2003. And it continues to be felt today, as the US Conference of Catholic Bishops wages a newly launched national campaign to end the use of the death penalty in the United States.

There will be many grand eulogies to mark the passing of Pope John Paul II. But none will be more eloquent than the ongoing campaign to bar the barbaric practice of state-sponsored execution. Perhaps John Paul II was not the most modern pope, but he recognized the progress of society and moral teaching when he preached that, “Modern society has the means of protecting itself, without definitively denying criminals the chance to reform.”