I’ve gotten a lot out of all of the spiritual books I’ve read, all different but all brilliant -
Confessions by St Augustine,
Imitation of Christ by Thomas a Kempis,
Ascent of Mount Carmel by St John of the Cross,
On Loving God by St Bernard of Clairvaux,
Practice of the Presence of God by Brother Lawrence,
Little Flowers of St Francis by Brother Ugolino.
Many years ago, it was *Mere Christianity *by C.S. Lewis. I read it as a young adult beginning to take the faith seriously, and it was a great help. Shortly after that, The Way, by Josemaria Escriva. It formed my attitudes toward life.
More recently, I Believe In Love, by Fr. Jean C.J. d’Elbee. It’s a wonderful exposition of the vastness of the love of God. Very helpful to reduce fear as one grows older and begins to look toward the last things.
I don’t know about “the most impact” but a book I think a lot about is James Martin, SJ’s My Life With the Saints. I have recommended it in response to several threads in CAF.
I don’t know that it would be considered a “spiritual” book, it’s fiction, but it is Catholic fiction. I have read and loved Pierced by a Sword, by Bud Macfarlane, about 5 times over the past 10 years. It was absolutely pivotal in my Faith formation and knowing what type of life I wanted to live and what types of people I wanted to surround myself with.
I’ve always considered it comfort food for my soul when I’m going through a rough time - it’s hard to explain, but I’ve just always loved this book so much.
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