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.
The second volume in Karl Rahner's series is an excellent work of theology, exploring the often overlooked but vitally important topic of ecclesiology. One of the things I admire a great deal about Fr. Rahner's writings is that, like Karl Barth, it is clear that theology is, for him, far more than just an intellectual exercise. He is writing for the Church as someone who is deeply invested in the Church. His love for God's people shines through on every page and makes a good work that much better.