By gathering the members of the Roman Curia for Lenten spiritual exercises this week, Pope Francis is participating in a tradition that stretches back more than 80 years, to the pontificate of Pius XI.

The Roman Curia are on retreat Feb. 22-27 on the theme "Servants and prophets of the living God," preached by Fr. Bruno Secondin, a Carmelite. The spiritual exercises will focus on Elijah and the Church's prophetic role, and they are being held in Ariccia, adjacent to Albano Laziale.

The Roman Curia's practice of spiritual exercises is modeled on St. Ignatius of Loyola's spiritual exercises. Pius XI was a great admirer of the founder of the Society of Jesus, proclaiming him patron of spiritual exercises in 1922.

In 1929 the same Pope issued the encyclical Mens Nostra on the promotion of the spiritual exercises, in which he also made public the decision to hold annual spiritual exercises in the Vatican.

The spiritual exercises then become a fixed annual meeting for the Roman Curia. In the beginning, they were preached during the first week of Advent, and on a few occasions they were supplanted.

In 1963, Bl. Paul VI decided it was better to move the exercises to Lent, and from 1964 on the spiritual exercises have taken place in the penitential season leading to Easter.

The preacher for the spiritual exercises is selected by the Roman Pontiff, and examining the list one finds that Pius XI and Venerable Pius XII both typically chose Jesuits; and St. John XXIII designated a Jesuit, a bishop, a parish priest, and the Apostolic Preacher.

The first non-Italian preacher was Bernard Haering, a Redemptorist from Germany chosen by Bl. Paul VI. Montini was also the first to select a cardinal: Karol Wojtyla, who preached in 1976 on "Christ, a sign of contradiction."

Since Bl. Paul VI's pontificate, having been selected to preach to the Roman Curia has also signaled a career jump: preachers who later became cardinals include Dezza, Javierre Ortas, Pironio, Anastasio Ballestrero, Carlo Maria Martini, Lucas Moreira Neves, James Hickey, Georges Cottier, Ersilio Tonini, Jorge Medina Estevez, Tomas Spidlik, Christoph Schonborn, Francois-Xavier Nguyen van Thuan, and Angelo Comastri. And Mariano Magrassi, Bruno Forte, and Enrico dal Covolo were appointed bishops shortly after they had preached the Lenten spiritual exercises for the Roman Curia.

In 1983, Cardinal Joseph Ratzinger, preached on the meaning of Lent, also discussing the way Christ was described as a character of the past by the historical-critical method of studying scripture.

Those reflections are the seed of Benedict XVI's three-volume work Jesus of Nazareth.

Under Benedict XVI, preachers of the spiritual exercises including Cardinal Francis Arinze; Cardinal Albert Vanhoye; Cardinal Giacomo Biffi; Cardinal Gianfranco Ravasi; Fr. Enrico dal Covolo; Fr. Francois-Marie Lethel; and Cardinal Laurent Monsengwo Pasinya.

Last year, Pope Francis selected Fr. Angelo De Donatis, who preached on "the purification of the heart."