Pope Francis blows a kiss to faithful after celebrating his first Palm Sunday Mass in St. Peter's Square at the Vatican, Sunday, March 24, 2013. (Gregorio Borgia/AP)

In the past week, the world witnessed the transition to the 265th successor to St. Peter, when Cardinal Jorge Mario Bergoglio S.J. of Argentina, the first elected from the Americas, and the first Jesuit, became head of the Roman Catholic Church, Pope Francis. There are two responsibilities that he holds: leader of the institutional church that is a locus of power—a church that engages in the world and is subject to all of the vagaries and temptations of the human condition; and inspirer of the church of the Spirit, a church that transcends the categories of earthly engagement, offering solace and hope to those embracing its prayers and spiritual practices.

It is about this second role that I reflect here, having been part of the U.S. delegation led by Vice President Joe Biden, to participate in the inauguration Mass of Pope Francis. I was moved by the new “style” he has exhibited, and, particularly, by his call for a “vocation of protection” and insistence on a shared responsibility to one another.

For me, last Tuesday’s Mass of Inauguration of the Petrine Ministry was marked by its familiarity. Notwithstanding the gathering of world leaders, including so many of different faiths in attendance, the service did not have the aura of coronation. Rather, for those of us practicing Catholics, we were, again, part of an act that anchors our week, one that provides order and focus for our lives. Every Sunday, we move through the liturgy in predictable and consistent ways. There is little variation. The readings change week-to-week, but in a regular cycle of repetition. Indeed, there was a modesty to the moment of this familiarity. We were brought together as much by the bedrock practice of our faith as we were to witness an almost unprecedented transition of power of a 2,000-year-old institution.

This “modesty” has been much noted--with the new pope’s choice of mitre, cross and ring, and the simplicity that has characterized his public life heretofore--and seems to be following on so far in his pontificate. And of course it is reflected in the name he has chosen.

In explaining his choice of name, he has described his reactions once it became clear he had been elected:

“I was seated next to…Cardinal Cláudio Hummes…And when the votes reached two-thirds, there was the usual applause, because the Pope had been elected. And he gave me a hug and a kiss, and said: “Don’t forget the poor!” And those words came to me: the poor, the poor. Then, right away, thinking of the poor, I thought of Francis of Assisi….Francis is also a man of peace. That is how the name came into my heart: Francis of Assisi. For me, he is the man of poverty, the man of peace, the man who loves and protects creation….”

Within any Mass, and true for the inaugural one as well, the creative moment in the service is the homily--when the presider offers personal reflections on the scriptural text of the day. And it happened that this day, March 19, was the feast of St. Joseph. In a prayer offered during the Mass, we are reminded that Joseph was a “just man…set as a wise and faithful servant in charge of [the] household…to watch like a father over your Only Begotten Son.”

Thus, in his homily, Pope Francis acknowledged the role that Joseph plays:

“…the mission which God entrusts to Joseph: he is to be the custos, the protector. The protector of whom? Of Mary and Jesus; but this protection is then extended to the church…” Joseph, in the Catholic tradition, is the protector of us all.

What is Pope Francis asking the rest of every one of us? Of course he refers to protecting each other, and together to protect the church—the venerable institution that has provided a source of consolation and meaning for individual human lives throughout these past two millennia. But he also refers to the commitment each of us makes to be the “protector” of each other.

In fact, in his homily he refers to “the vocation of being a protector.” This vocation “means protecting people, showing loving concern for each and every person, especially children, the elderly, those in need, who are often the last we think about…those whom Matthew lists in his final judgment on love: “the hungry, the thirsty, the stranger, the naked, the sick and those in prison.”

But the message takes us further: to the insistence of shared responsibility, to each other and to the earth. “In the end, everything has been entrusted to our protection, and all of us are responsible for it,” he enjoins us. This conviction was present in his first words when he appeared on the balcony: “And now, together, let us start this road: bishop and people. This [new] path of the Church of Rome…A path of brotherhood, of love, of trust between us. Let us pray always for ourselves: one for the other.” This message of shared responsibility is one that should--indeed, must--animate all people as well as their institutions in this interdependent world.

John J. DeGioia is president of Georgetown University.