On 21 July 1550, Pope Julius III issued the Bull Exposcit Debitum [The Duty Requires] giving final approval to the foundation of the Society of Jesus/Jesuits. This document continues to be the defining text for the mission and charism of the Society of Jesus today.

The Bull clearly reflects the spirituality of the Jesuit as a “soldier of God” and “to strive especially for the defense and propagation of the faith”. Exposcit Debitum also expresses the particular obedience the Jesuit owes to the Holy Father as:

For the sake of greater devotion in obedience to the Apostolic See, of greater abnegation of our own wills and of surer direction from the Holy Spirit, we have nevertheless judged it to be supremely profitable that each of us and any others who will make the same profession in the future should, in addition to that ordinary bond of the three vows, be bound by this special vow to carry out whatever the present and future Roman Pontiffs may order which pertains to the progress of souls and the propagation of the faith; and to go at once, without subterfuge or excuse, as far as in us lies.

The language of the Bull reflect both St. Ignatius’ belief that the Protestant Reformation was a threat to the Catholic Church, thus the need to defend the faith, and Pope Julius’ understanding that the Jesuits would be instrumental in spreading the faith to non-Christian lands, thus the need to propagate the faith.