This monograph seeks to answer the question why Melchizedek, who is a minor figure in the Old Testament, is selected by the author of the Epistle to the Hebrews to represent the priesthood of Christ. In the course of his study, Professor Horton surveys the traditions about Melchizedek from the Old Testament period, in Philo, Josephus and Qumran, to the later sources in Rabbinical and patristic writings and the Gnosticism. The book concludes with a critical examination of the claims made for the dependence of Hebrews on the Qumran figure and tradition. The author finally rejects this interpretation in favour of a source and background for Hebrews in an independent and largely original interpretation of the Old Testament passages.