The Old Testament canon is both historical and theological problem. Until the 1970s, it was almost exclusively the historical side that interested scholars when it interested them at all. Introductions' to the Old Testament tended to treat it at the very end, as a subject that mattered rather little. The work of B. S. Childs and J. A. Sanders in different ways propelled the canon into the spotlight of interest among Old Testament scholars for the first time, and it is now an important focus for much new research, surveyed in two major recent collections of essays The Canon Debate and The Biblical Canons. Rex Mason himself, who has done so much important work on the Twelve, had raised the question, though without wishing to resolve it in a Childs-like way. Old Testament or Hebrew Bible was a paper originally delivered to a Faculty seminar in Oxford and subsequently published in a series intended for teachers of Religious Education in schools.