“Devil’s advocate” began as a name for a role in the Catholic Church’s canonization process. The expression reflects the Latin *advocatus diaboli*, or “advocate of the devil,” though the official was known as the Promoter of the Faith. The office is traditionally dated to 1587, under Pope Sixtus V, when the Church was organizing a more formal process for examining candidates for sainthood. The precise first use of the Latin nickname is difficult to establish, but its association with these proceedings dates to the early modern period.
The official’s job was to scrutinize a candidate’s case: question claims about virtue and miracles, examine evidence, and raise objections before a decision was made. This was meant to guard against enthusiasm or weak testimony, not to oppose sainthood for its own sake. The role is often described as having been abolished in 1983, but that can be misleading. Pope John Paul II’s reforms changed and streamlined the canonization process; the Promoter of the Faith remained, though the former adversarial role was substantially altered.
The popular image of a church official literally defending the Devil is more theatrical than historical. Nor was the advocate supposed to smear candidates or manufacture objections. The point was to test a proposed case by giving its weaknesses a serious hearing. That practical idea made the phrase easy to carry beyond church proceedings. By the 18th century, English speakers were using “devil’s advocate” figuratively for someone who argued against a position to test it, whether or not that person truly held the opposing view.
Today, the phrase can describe a useful habit in a discussion or a frustrating interruption, depending on the setting. “I agree with the proposal, but let me play devil’s advocate: what happens if costs rise?” In a meeting, someone might say, “We need a devil’s advocate to spot the risks before we commit.” The expression endures because it gives a familiar name to a valuable challenge: testing an idea before trusting it.