Ten years after the Second Vatican Council the novel Die Vision des Papstes: Erzählung was published simultaneously by Catholic and Protestant publishers under the pseudonym ‘Sebastian Knecht’. The author of the work was the former official observer of the Protestant Church of Germany (EKD) to the Council, the Heidelberg professor Edmund Schlink, who retired in 1972. The fact of his authorship was known only by a few friends prior to his death; following the death of her husband Mrs Irmgard Schlink revealed the pseudonym. Thus today, one may first examine the historical reasons why Schlink wrote the book. Further, its theological content makes possible a clearer view of the strengths and problems of the particular way to the unity of the Church Schlink recommends in the story. Finally, the effect of the work raises the question if it was meaningful to suggest a solution to ecumenical problems by means of belles lettres.