 He was the possessor of a large library which contained many valuable manuscripts.Epstein is the author of the "Ḳadmut ha-Tanḥuma," a review of S. Buber's edition of the Midrash Tanḥuma (Presburg, 1886), and of "Mi-Ḳadmoniyyot ha-Yehudim," which contains (1) treatises on Jewish chronology and archaeology, and (2) a revised and annotated edition of Midrash Tadshe (Vienna, 1887).He also wrote