After a weeklong spiritual retreat outside of Rome, Pope Francis expressed his gratitude to the priest who led the reflections, saying that although it's not always easy to preach to priests, seeds have been planted.

"On behalf of all of us, I too would like to thank the father for his work among us during the spiritual exercises," Francis said after his return to Rome Feb. 27.

"It's not easy to give exercises to priests, right?  We're a bit complicated, all of us, but you succeeded in sowing seeds," he said, and prayed that these seeds would continue to grow.

Francis' words were directed to Carmelite priest Fr. Bruno Secondin, who preached on the theme "Servants and prophets of the living God" during the Roman Curia's Feb. 22-27 Lenten retreat.

This year's spiritual exercises focused on the figure of Elijah and the Church's prophetic role. They are were held in the Casa Divin Maestro center in Ariccia, Italy, which is adjacent to Albano Laziale and sits roughly 16 miles outside of Rome.

It is the second consecutive year in which Pope Francis wanted the Curia's spiritual exercises to be held outside of the Vatican, in order to foster the spiritual aspect of the retreat and avoid the temptation to continue working.

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.

Since then the spiritual exercises have become a fixed annual meeting for the Roman Curia.

Originally preached during the first week of Advent, the exercises were moved to the Lenten season by Bl. Paul VI in 1964, and have taken place the penitential season leading to Easter ever since.