My “famous-infamous” statement (p. 21 [28]) simply means that it is not possible to establish first that Christ’s crucifixion is the saving event and then to believe (for that would mean seeing Jesus as Christ before believing him to be so), but that the crucifixion can be seen as the saving event (and Jesus as Christ) only in faith; though naturally in such a way that I first believe and then confirm that the crucified one is Christ. To believe in Christ and to understand the saving event are one and the same thing.

–Rudolf Bultmann, Marburg, November 11-15, 1952, Karl Barth/Rudolf Bultmann Letters/1922-1966.