A single key can best answer all of these questions: Francis’ longstanding identity as a Jesuit priest.

It’s an all-encompassing personal and professional definition that the former Cardinal Jorge Bergoglio brought with him from Buenos Aires, and one that continues to shape almost everything he does as Pope Francis.

“He may act like a Franciscan but he thinks like a Jesuit,” quipped Fr. Thomas Reese, a fellow Jesuit who is a columnist for National Catholic Reporter.

In fact, it would be easy to mistake the Pope for a Franciscan, given his emphasis on helping society’s outcasts and his decision to become the first pope to take the name of St. Francis of Assisi, the patron saint of the poor. Yet he’s the first pope from the Society of Jesus, the religious community whose worldly wise intellectuals are as famous as its missionaries and martyrs.

Indeed, behind that “Jesuit” label lies a centuries-old history and a unique brand of spiritual formation that go a long way toward understanding who Francis is and where he is taking the Church.

From his passion for social justice and his missionary zeal to his focus on engaging the wider world and his preference for collaboration over peremptory action, Francis is a Jesuit through and through. And as the first Jesuit pope, he brings sharply etched memories of being part of a community that’s been viewed with deep suspicion by Rome, most recently by his own predecessor, Pope Benedict XVI.

Jesuit priests are explicitly discouraged from becoming bishops, much less pope, and that outsider’s sensibility helps to explain Francis’ almost breezy willingness to dispense with centuries of closely guarded and cherished tradition.

“We never imagined that a Jesuit could become pope. It was an impossible thing,” said Fr. Antonio Spadaro, a Jesuit who conducted a book-length interview with the Pope and knows him well. “It sent me into a crisis, in a sense, when he was elected. We Jesuits are supposed to be at the service of the pope, not to be a pope.”

What is a Jesuit?

The Society of Jesus, as it is formally known, was begun in the 1530s by Ignatius of Loyola, a Basque soldier who underwent a profound religious transformation while convalescing from war wounds. Ignatius composed the Spiritual Exercises, used to guide the Jesuits’ well-known retreats, and in 1540, along with six other theology students at the University of Paris, he won recognition from Pope Paul III as an official Church order.

In many ways, the Jesuits are like other religious orders, such as the Franciscans or Dominicans. Jesuits take vows of poverty, chastity and obedience, and they live in community, sharing everything. Like other religious-order priests, but unlike diocesan priests, they are not ordained to a particular geographic diocese to serve the local bishop.

Jesuits are an all-male order; there are no Jesuit sisters. The society has an almost military-style structure and ethos, its shock troops willing to go wherever and whenever the Church needs them. They are “contemplatives in action,” in the words of St. Ignatius, and have an especially lengthy period of study and spiritual preparation before taking final vows. From the first two years as a novice to ordination can take 13 years or more.

Even then, the process is not complete. After another few years, Jesuits spend a year revisiting their novitiate and then take final vows, including a special fourth vow of obedience “in regards to mission” to the pope.

If the Church needs priests to re-convert souls lost to the Protestant Reformation, the Jesuits are on it. If they are needed to bring Catholicism to new lands, such as Asia or Latin America, they’ll buy a one-way ticket. To advance the Church’s mission, the Jesuits have shaped generations of minds through universities such as Georgetown, Fordham and Boston College.

Despite their simple beginnings, the Jesuits quickly became (and remain) the largest order in the Catholic Church. Its leader was called “the Black Pope” for his distinctive, austere black cassock as well as his perceived power. It’s little wonder the cardinals never wanted to elect a Jesuit as the actual pope — and no wonder the society wound up a target of the Church it was called serve.

In 1773, Catholic monarchs jealous of the Jesuits’ influence and independence pressured Pope Clement XIV to suppress the order, declaring the society “perpetually broken up and dissolved.” Yet in 1814, the order was restored — an anniversary that Jesuits are celebrating this year along with the election of one of their own to the throne of St. Peter.

In the 1960s, the Jesuits collectively opted for a decisive shift to emphasizing working on behalf of the poor and for social justice. In the developing world, that put Jesuits on the frontlines of popular movements for the poor, such as liberation theology, and led to martyrdom at times; in El Salvador, six Jesuits, along with their housekeeper and her daughter, were brutally executed by a Salvadoran military unit in 1989.

At the same time, the Vatican under Pope John Paul II — aided by his doctrinal czar, Cardinal Joseph Ratzinger — investigated, sanctioned and sometimes silenced Jesuit theologians who were considered too eager to marry the Gospel to suspect social movements.

Jesuits have also fallen victim to what some call the “white martyrdom” at the hands of the pope. As recently as 2005, Reese was forced out as editor of the Jesuits’ America magazine when his longtime foe, Ratzinger, was elected Pope Benedict XVI and ordered the society to fire him.

What kind of a Jesuit is Francis?

As a Jesuit in Argentina, ordained in 1969, Jorge Bergoglio also found himself in the midst of all this tumult. He had initially joined the Jesuits in the 1950s because he was “attracted to its position on, to put it in military terms, the frontlines of the Church.” But little did he know how serious the combat would become.

The Argentine “Dirty Wars” erupted during the 1970s, and the violence that overtook the country also threatened many priests — especially Jesuits — even as the regime co-opted much of the hierarchy. Bergoglio was made superior of the Argentine Jesuits at the age of 36, thrown into a situation of internal and external chaos that would have tried even the most seasoned leaders.

“That was crazy. I had to deal with difficult situations, and I made my decisions abruptly and by myself,” Francis said last year, acknowledging that his “authoritarian and quick manner of making decisions led me to have serious problems and to be accused of being ultraconservative.”

Bergoglio fully embraced the Jesuits’ radical turn to championing the poor, though he was seen as an enemy of liberation theology, and many Jesuits, while others in the order were devoted to him. He turned away from devotional traditionalism but was viewed by others as still far too orthodox. Critics labeled him a collaborator with the Argentine military junta even though biographies show that he worked carefully and clandestinely to save many lives.

None of that ended the intrigue against Bergoglio within the Jesuits, and in the early 1990s he was effectively exiled from Buenos Aires to an outlying city, “a time of great interior crisis,” as he’s put it.

In classic Jesuit tradition, however, Bergoglio complied with the society’s demands and sought to find God’s will in it all. Paradoxically, his virtual estrangement from the Jesuits encouraged Cardinal Antonio Quarracino of Buenos Aires to appoint Bergoglio as an assistant bishop in 1992.

“Maybe a bad Jesuit can become a good bishop,” an Argentine Jesuit said at the time.

In 1998, Bergoglio succeeded Quarracino as archbishop. In 2001, John Paul made Bergoglio a cardinal, one of just two Jesuits in the 120-member College of Cardinals.

His rise in the hierarchy, however, only seemed to cement suspicions about him among his foes among the Jesuits. During his regular visits to Rome, Bergoglio never stayed at the Jesuit headquarters but rather at a clerical guest house with other prelates. In the 2005 conclave that elected Benedict XVI, Bergoglio was the runner-up, a near-miss that left many Jesuits breathing a sigh of relief.

So when Bergoglio was chosen as Pope in March of 2013, one could almost hear the collective gasp in Jesuit communities around the world.

“The fact that he had been somewhat rejected, internally, by the Jesuits, if not for that he probably would not have become a bishop,” said Fr. Humberto Miguel Yanez, an Argentine Jesuit like Francis, who heads the moral theology department at the Gregorian University in Rome — a Jesuit school sometimes called “the pope’s Harvard.”

And if he had not become a bishop he would not have become a cardinal and, ultimately, Pope, since the College of Cardinals by tradition chooses each successor to St. Peter from among their own ranks.

“The stone that the builders rejected,” Yanez quipped, citing Jesus’ words in the Gospel of Matthew, “became the cornerstone.”

What will a Jesuit pope mean for the Church?

Now, of course, all is forgiven, and then some. Francis is a “brother among brothers,” as the current head of the order, Fr. Adolfo Nicolas, put it, and Francis has made a point of highlighting the importance of the Jesuits and the Ignatian way for the Church.

Francis also knows how much the Jesuits are still resented by some corners in the Church, and especially in the Vatican, but he has not let that alter his own deeply Jesuitical style.

Last December, he circumvented the usual protocols to canonize one of Ignatius’ original companions, Peter Favre, whom Francis has praised for being “in dialogue with all, even the most remote and even with his opponents.” The same could be said for Francis’ papal style. He lives simply, rejecting the traditional papal apartments to live in a small community inside a Vatican guest house.

The Pope also preaches forcefully that other clerics, and especially the hierarchy, should eschew the perks and privileges of their office and instead learn to act and live like the servants of their flock he says they’re called to be.

Francis’ pastoral style extends to his mode of governance. One of his first actions as Pope was to name a council of eight cardinals from around the world — none of them from the dysfunctional Roman Curia — to serve as a kitchen Cabinet, much the way Jesuit superiors operate. He has used a similar model for tackling specific tasks as well, such as overhauling the Vatican’s finances.

“The whole concept of setting up committees, consulting widely, convening smart people around you — I believe that is how Jesuit superiors probably function,” said Ken Hackett, the U.S. ambassador to the Holy See. “Then you make the decision.”

This sort of discernment — listening to all and contemplating everything before acting — is a cardinal virtue of the Ignatian spirituality that is at the core of Francis’ being and his commitment to a “conversion” of the papacy as well as the entire Church. 

“The journey from Bergoglio to Francis may mean that the journey is not yet complete,” as papal biographer Paul Vallely writes.

But that also means that it’s hard to say exactly what will come next. Francis is shrewd and he has repeatedly praised the Jesuit trait of “holy cunning” — that Christians should be “wise as serpents but innocent as doves,” as Jesus put it. The Pope’s openness, however, also a signature of his Jesuit training and development, means that not even he is sure where the spirit will lead.

“I confess that, because of my disposition, the first answer that comes to me is usually wrong,” Francis said in a 2010 interview.

“I don’t have all the answers. I don’t even have all the questions. I always think of new questions, and there are always new questions coming forward.”