Perhaps less well known is his contribution to the spiritual tradition of post-Tridentine Catholic spirituality. In this volume, two of his most influential ascetical works have been produced for the first time in modern English translations. The Mind's Ascent to God (1614) is a treatment of the steps involved in ascending to union with God, written in the tradition of Bonaventure and John Climacus. Characterized by Pierre Pourrat as a work of "optimistic piety, overflowing with divine love," it became an almost instant success, with five Italian editions done in the first year of publication. By 1930 some sixty editions in over fourteen different languages had promulgated what is arguably Bellarmine's most beautiful and inspiring spiritual work.

In 1619 he published his last ascetical piece, The Art of Dying Well, which is included here in its entirety. Drawing on the medieval genre of books on death, it blended a traditional approach with elements of new piety of the Renaissance and Counter-Reformation. Together these two works, introduced masterfully by John Donnelly, provide a deep insight into the piety of a great figure.