Karl Rahner, SJ (March 5, 1904 — March 30, 1984) was a German Jesuit and theologian who, alongside Bernard Lonergan and Hans Urs von Balthasar, is considered one of the most influential Roman Catholic theologians of the 20th century.
He was born in Freiburg, Germany, and died in Innsbruck, Austria.
Before the Second Vatican Council, Rahner had worked alongside Yves Congar, Henri de Lubac and Marie-Dominique Chenu, theologians associated with an emerging school of thought called the Nouvelle Théologie, elements of which had been criticized in the encyclical Humani Generis of Pope Pius XII.
A deep, penetrating and eerily insightful guide to theologically-grounded Christian spirituality, especially helpful for thoughtful introverts. I especially found his thoughts on prayer, silence and mystical experience of the Holy Spirit uplifting, nuanced and applicable. Definitely my favourite book on spirituality and is well worth a read, especially for those who may tend towards cynicism concerning spirituality or those who may see it as a woolly, nebulous concept. Rahner forensically cuts through the murky waters and dissects the true essence of spirituality. His reflections on spirituality are, for most writers in this area, uncharacteristically, but very much helpfully, systematic and coherently structured. The reflections are also concrete, highly relatable and directly applicable. "Encounters with Silence" (especially the chapter entitled "Prayer") is also worth a read.