ROME – History’s first Jesuit pope on Monday took to Twitter to praise the founder of the Society of Jesus, Spaniard St. Ignatius of Loyola. In a message sent out to his 35 million followers, Pope Francis called on them to imitate the saint by being at the service of others.

Loyola, founder of the Society of Jesus, often called the Jesuits, was a Spanish soldier-turned-mystic who died in 1556 at the age of 64. He was beatified in 1609, and declared a saint on March 12, 1622. His feast day is celebrated on July 31, which is the reason why Francis sent out the tweet on Monday.

Ever since the beginning of his pontificate, Pope Francis has marked the date in some way. For instance, back in 2013, only months after his election, he went to Rome’s Church of the Gesù, the mother church of the Jesuits, where he said Mass.

During his homily, he prayed that he and all his fellow Jesuits would receive “the grace of shame” for their failures, and the humility to recognize that whatever good they accomplish is really done by the Lord. He also prayed for Jesuit Father Paolo Dall’Oglio who was kidnapped in Syria on July 29, 2013.

In 2014, he marked the day by meeting the family of Dall’Oglio, and having lunch with them and a group of priests at the Jesuit headquarters for lunch.

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Beyond marking July 31st, Francis has held close ties with the Jesuits since his election, despite having had some issues with the order back in Argentina. During his foreign trips he makes the point of visiting the local Jesuit community, and has appointed several members of the order to key positions in the Vatican, recently including Archbishop Luis Ladaria Ferrer as the new head of the Congregation for the Doctrine of the Faith.

At present, the community Loyola founded is the leading men’s religious order in the Church, with some 16,740 Jesuits scattered across the four corners of the earth, including about 12,000 priests, 1,300 brothers, 2,700 scholastics, and 753 novices.

It’s because of his military past and the Jesuits’ missionary outreach that they’re often dubbed “God’s Marines.” Because of the power they’ve held in the past, their Superior General is informally known as “the Black Pope.”

With their emphasis on missionary work and intellectual pursuits, the Jesuits at times move on the margins of the Church, and for some of them it’s a point of pride to color outside the lines despite St. Ignatius’s allegiance to the Vatican and the pope.

In a 2013 interview with fellow Jesuit Father Antonio Spadaro, Francis said that when he decided to become a priest “three things in particular struck me about the Society: The missionary spirit, community and discipline. And this is strange, because I am a really, really undisciplined person.

“And then a thing that is really important for me: community,” the pope said. “I was always looking for a community. I did not see myself as a priest on my own. I need a community. And you can tell this by the fact that I am here in Santa Marta.”

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