The crypt forms an integral part of the overlying Chapel of Our Lady of Manresa. In his description of the Casa di Manresa, its founder Rosignoli explains that he sought to build a retreat house in which one could come to prepare for that which really matters, ‘la buona morte’ – a good death. Saint Ignatius of Loyola himself, in his Spiritual Exercises, urged his companions and those who undertook the experience of retreat to contemplate life from the perspective of the deathbed.

The contemplation of the ‘Four Last Things’ – Death, Judgment, Heaven, and Hell, that is the ‘ars moriendi' - would have animated the retreatants’ reflections during their stay in Casa Manresa. They would have reflected on their present life and its transient nature in the perspective of, indeed in preparation for, the life to come. Such a perspective is rooted in a long-standing Christian ascetical experience: this was accentuated in a world where death and its consequences were a more tangible and visible reality, and life seen as the ante-chamber of eternity.

The crypt is a particularly suitable place to evoke all these sentiments. Here, deep in the earth, priests came down to offer the Sacrifice of Calvary for the repose of all the Souls in Purgatory.

The crypt itself is of simple design, with one stone altar facing the main doorway. It is part of a vast complex of chambers underlying this baroque house. These underground chambers clearly included the services needed for the running of the retreat house. They include the kitchen, storage rooms, and laundry with its water supply directed from Wignacourt’s tower opposite Sarria Church.