The relation between revelation and tradition, which has been a crucial issue in Catholic theology, particularly since the Modernist crisis, has been clarified by the Constitution De revelatione of the Second Vatican Council. In the present work, Karl Rahner and Joseph Ratzinger, both Council periti, explore some of the speculative and historical foundations of the Constitution. For Rahner, revelation is the act whereby man's transcendent vocation to the super- natural is made clearly manifest by God in concrete historical events. The medium of his manifestation is the believer's response-whether explicit or not-to the Word incarnate in history and to the Spirit who acts pre-eminently through the historical reality of the Church. Thus is sketched a radically fresh approach to understanding the nature of salvation history in its relation to the life of the Trinity, to "secular" history, and to the history of religions in general. Joseph Ratzinger provides a historical corollary to Rahner's conclusions by a detailed appraisal of the arguments set forth at the Council of Trent in answer to the Reformers' emphasis on sola scriptura. Moving away from the thesis of J. R. Geiselmann, Ratzinger shows that while the Bible retains its central place in Christian belief, the concept of tradition implied by Trent nevertheless embraces more than merely the notion of the transmission of the scriptures. Tradition in its deepest sense is the Church's living consciousness of its faith in the revealing Word, and as such is the hermeneutical key to grasping the written word of the Bible.