This study examines the development of a new Lutheran doctrine of the soul's immortality in the course of the sixteenth century. After a brief sketch of the medieval and Renaissance background, I begin with Luther, whose eschatological thought has been much scrutinised, but without producing a lasting scholarly consensus. Against widely different recent interpretations, I argue that Luther's apophaticism and emphasis on the unspeakability and ungraspability of the post-mortem state should be recognised. Against a popular mid-twentieth-century theological position that sharply juxtaposed the resurrection of the body with the immortality of the soul, and attributed the same conviction to Luther, it must be affirmed that the Reformer saw the latter doctrine entailed in the former, and he understood both insights as articles of faith, of which reason could never be certain.

Analysing revisions between his Commentarius and Liber de anima, I show that Melanchthon's mature position was that the immortality of the soul could be recognised by reason without revelation, while belief in the resurrection of the body was a privilege of faith. Melanchthon's return to Aristotle and his admission of reason, however, must be seen in the context of a Lutheran law-gospel dialectic, and should not be regarded as compromising the older Reformer's theology.

In the second half of the sixteenth century, German Lutheran authors, including Melchior Specker, Andreas Musculus, Basilius Faber, Martin Mirus, David Chyträus and others produced a remarkably coherent body of literature in which they affirmed the soul's immortality. Superficially, the new orthodoxy seems closer to Lateran V than to Luther, but that is not the case. While patristic ideas and other factors were also in play, the three most profoundly formative influences shaping the work of second and third-generation Reformation theologians originated with Luther, Melanchthon, and a confessional commitment against the Catholic doctrine of purgatory. Philosophically, later-sixteenth-century authors were all students of Melanchthon. Theologically, however, Luther exerted a more profound influence on them, which I demonstrate by examining their arguments and prooftexts in general, and their treatment of three questions—soul sleep, knowledge of the righteous dead, and the appearance of departed souls on earth—in particular. The dissertation concludes with some reflections on the functions and consequences of the doctrine.