Timothy Radcliffe, Vatican

Photo courtesy RNS/CatholicVote.org.

A meme comparing Popes John Paul II, Benedict XVI and Francis. Photo courtesy RNS/CatholicVote.org.

As a millennia-old institution, the Vatican is accustomed to change at a glacial pace. But in the eyes of many outside the church — and even of some within it — the arrival of Pope Francis on the throne of St. Peter seems to have started nothing short of a revolution.

Even Francis himself, in his speech to Rome’s diocese on Monday, said that Christians not only can, but should, be “revolutionaries.”

Now, 100 days into his pontificate, a debate is brewing in Rome over whether Francis has set a distinctly different course from his predecessor, or whether the visible differences in style and personality between Francis and Benedict XVI mask a deeper theological and ideological continuity.