It is now axiomatic in Pauline studies that eschatology is central to the Apostle's theologizing. Any serious study of his thought must reckon with his belief about the future; it is pervasive in his thought.
Such was not always the case in critical studies of Paul, though. Indeed, it was not until the early 20th century that Pauline scholarship really began to wrestle with the eschatological dimension of Paul's letters. Albert Schweitzer is largely credited with establishing the importance of eschatology for the study of Paul, but, as far as I can tell, Geerhardus Vos was doing the same thing at about the same time. Vos' monumental volume, The Pauline Eschatology, was first published in 1930, the same year as the German edition of Schweitzer's influential The Mysticism of Paul the Apostle. In the foreword of the 1979 reprint of Vos' book, Richard Gaffin suggested that while Schweitzer is more frequently credited with "leading the way in bringing about a widespread awareness of the pervasively eschatological character of Paul's teaching," Vos did so more faithfully to Paul without some of the weaknesses Gaffin finds in Schweitzer's understanding of Paul's Christ-mysticism. Gaffin goes on to point out that Vos articulated many of the central issues in his 1912 essay, "The Eschatological Aspect of the Pauline Conception of the Spirit." Schweitzer, however, also raised the issue in that same year with his Paul and His Interpreters, in which he concluded that Paul's theology is essentially eschatological.
So, here's the question: Did Vos and Schweitzer place this initial emphasis on the importance of eschatology for Pauline theology simultaneously, or did one of them publish something prior to 1912 that should be credited as being the pioneer study on the matter? Some of you Paul scholars out there, help me out.