The German-born philosopher and writer Franz Rosenzweig (1886-1929) was important for his formulations and definitions of Jewish-Christian relations.

Franz Rosenzweig was born at Kassel on Dec. 25, 1886. Rosenzweig first took up medicine; but, not finding this to his liking and discovering also a certain dichotomy in his life, he turned to the study of history and philosophy. He followed this with law studies. His early upbringing and education inclined him more and more to conversion to Christianity. However, in 1913 he attended an Orthodox Day of Atonement service and suddenly decided to halt his drift to Christianity and to adopt seriously the religion of his Jewish forefathers. It was these three themes, Christianity, Judaism, and Atonement (redemption), that formed the kernel of his life achievement in religious research.

While serving in the German army during World War I, Rosenzweig initiated a lively correspondence with Eugen Rosenstock concerning the relationship of...