Opinion by Matt Emerson, special to CNN

(CNN) - Is Andrew Garfield, star of films such as “The Social Network” and “The Amazing Spiderman,” considering the priesthood?

Last month, paparazzi snapped a picture of Garfield walking as he carried “The Jesuit Guide to (Almost) Everything,” the Rev. James Martin’s insightful overview of Jesuit life and spirituality.

According to reports, he’s consulting the book as he prepares to play a Jesuit in a film adaptation of “Silence,” a novel about Catholic missionaries in Japan.

Garfield’s reading material – and the movie he’s studying for – captures the continuing cultural impact of the 474-year-old Catholic religious order officially known as the Society of Jesus.

Sometimes called "God's Marines" (not all appreciate the nickname) for their willingness to go to the frontlines of faith, Jesuits form the largest order of Catholic priests in the church, with approximately 18,000 members worldwide. And, at a time when most religious orders are shrinking and pining for new candidates, the Jesuits say inquiries about joining their ranks are surging.

What explains the Jesuits’ enduring appeal?

Much of it has to do with their academic legacy. In the United States alone, there are 60 Jesuit high schools and 28 Jesuit colleges and universities. They are part of a network of secondary and post-secondary institutions that stretch from Los Angeles to Lagos to Tokyo. A good number of those schools are named after the founder of the Society of Jesus, St. Ignatius of Loyola.

Born in Spain in 1491, Ignatius – then Iñigo Lòpez de Loyola – was groomed for a conventional path in service of the Spanish crown.

Known as something of a ruffian and a ladies’ man, Inigo entered the military and, in 1521, encountered the French at the Battle of Pamplona, a fight that left his right leg badly wounded by a cannonball.

With time to pray and reflect, Inigo underwent his remarkable conversion from swashbuckling soldier to spiritual pilgrim. A new man and now disciple, Inigo adopted a new name: Ignatius, which some say marked his newfound respect for St. Ignatius of Antioch.

In addition to Ignatius’ captivating conversion, his work “The Spiritual Exercises,” continues to inspire contemporary Catholic movements in education and prayer, and serves as the foundation for all Jesuit ministries. The exercises are essentially a retreat manual, a series of guided meditations that enable people to experience the love of God and strengthen their relationship with Christ.

With the aide of the Spiritual Exercises, which members of the Society of Jesus are required to periodically revisit, a steady stream of Jesuits from nearly every country and background have shaped the culture, politics, and events of their day.

There’s Matteo Ricci, the 16th century missionary to China, a polymathic priest and a groundbreaking figure in connecting Asian and European cultures.

There’s Gerard Manley Hopkins, the nineteenth century English poet, whose verse is regarded as some of the best of the Victorian era and regularly included in poetry anthologies.

And there’s Pierre Teilhard de Chardin, the French Jesuit born in 1880 who, as a paleontologist, was instrumental in discovering and examining “Peking man,” and who, as a theologian, remains notable for his efforts to synthesize science and Christianity.

Their lives demonstrate the ways that a distinctly religious worldview can speak to the world’s needs, an emphasis on practicality that is thoroughly Jesuit in origin. "Contemplation in action," runs one well-known Jesuit motto.

“Jesuits, as their tradition insists, can be found in almost every country, in almost every workplace imaginable,” Jonathan Wright writes in his book, “God’s Soldiers: A History of the Jesuits.”

That includes war zones, retreat houses, business schools and chemistry labs. There are Jesuit doctors, lawyers, engineers and psychologists, as well as artists and television producers.

In this variety and geographic reach, the words of one early Jesuit, Jerónimo Nadal, ring true: “The whole world . . . is our house.”

Today, the Jesuits are as well-known as at any time in their history. This popularity starts at the very top of the Catholic Church with Pope Francis, himself a Jesuit for more than 50 years.

In an extensive interview published last September in America magazine, Francis spoke at length about his Jesuit identity and background.

He decided to join the society as a young man in Argentina, the Pope said, because he admired its "missionary spirit, community and discipline," even though he was himself not very disciplined.

A key to understanding Pope Francis

He later came to appreciate Jesuits' open-mindedness and willingness to see God in all things, great and small, Francis said.

"The Jesuit always thinks, again and again, looking at the horizon toward which he must go, with Christ at the center. This is his real strength. And that pushes the Society to be searching, creative and generous."

Catholic leaders who know the Pope well say his Jesuit training is the "key to understanding" Francis. "Pope Francis is the quintessential Ignatian Jesuit,” said Cardinal Sean O'Malley of Boston, one of the Pope's closest confidants.

For instance, O'Malley said, consider the Pope's decision to wash the feet of a group of prisoners on Holy Thursday in 2013, just after his election as pontiff, instead of following Vatican tradition and celebrating a Mass at St. John Lateran's Archbasilica.

"With a simple gesture, the Holy Father was challenging core assumptions about power, authority and leadership," O'Malley said, adding that his actions "jostled" Catholics out of complacency.

Francis may be the the most well-known Jesuit, but others engage the culture in influential ways as well.

Martin, author of “The Jesuit Guide to (Almost) Everything,” appears regularly on Comedy Central’s “Colbert Report” to discuss topics like heaven and hell, social justice and the latest news from the Vatican. And Jesuits can often be relied upon to converse about more far-out topics – like really far out.

For example, Jesuit brother Guy Consolmagno, who recently won the Carl Sagan Medal for communicating science to the public, has co-written a forthcoming book titled “Would You Baptize an Extraterrestrial?” a question that only a Jesuit could love. (Pope Francis, for the record, says yes.)

Given its history and global presence, you might think the Society of Jesus would closely guard its legacy. But this is one area where the Catholic order breaks with typical expectations.

A hallmark of Ignatian spirituality is the emphasis on remaining indifferent. That doesn't mean apathy or disinterest, but rather a radical availability to the will of God. As Jesuits say, this “Ignatian indifference” is about freedom from attachments that displace God as the center of one’s life.

How to really measure the 'Francis effect'

That freedom has imbued the Society of Jesus with a spirit of re-creation for five centuries, and I wouldn't be surprised if it continues to inspire Jesuits for the next 500 years.

One day my children might enjoy a new technology created by a Jesuit who works at Google or a Jesuit whose path to the priesthood was perhaps inspired by a movie starring a certain Hollywood celebrity.

Father Andrew Garfield? Seems impossible, right?

Not exactly. Read the biography of Ignatius, and you’ll know why.

Matt Emerson blogs for the Jesuit magazine America and teaches theology at Xavier College Preparatory, a Jesuit high school in Palm Desert, California. The views expressed in this column belong to Emerson.