VATICAN CITY — Days after the election of Pope Francis, word reached the Vatican press office that the new pontiff was unexpectedly celebrating morning Mass. Other popes had presided over morning services, too, but as the world (and the Vatican press office) would soon realize, Francis did things his own way.

This Mass was offered in the small chapel of the Vatican guesthouse where Francis had chosen to live — not, as in years past, at the ornate Apostolic Palace. His audience was not the cardinals of the Roman Curia, but gardeners, janitors and Vatican office workers. And Francis was not merely presiding, as had Pope John Paul II. He was preaching, without notes, as if he were a simple parish priest.

If one with a big message.

“The church asks all of us to change certain things,” Francis said during one of his morning homilies, as he invoked a Scripture reading from St. Paul. “She asks us to let go of decadent structures — they are useless.”

The symbolism of the morning services, which Francis now holds four times a week, is clear: a humbler papacy, where the pope is foremost a pastor to the flock, not a king. But a humbler papacy hardly means humbler papal ambitions. Francis is not just trying to change the Roman Catholic Church. He seems determined to change the world.