To understand how it came about that a distinct line of demarcation was drawn between canonical and apocryphal books, a preliminary consideration is necessary, viz. how the _idea of a Canon_ arose. We are faced with the fact that before the beginning of the Christian era there was a large body of literature in existence some books of which were held in higher honour than the rest, though they did not differ in kind, but only in their degree of sacredness, from these books. It was from this fact that the idea of a Canon arose; that is to say, the idea of a Canon assumes the existence of a number of books from which are selected those which finally become canonical. Between this and the fixing of a Canon there is clearly a great difference. To show that a distinction has to be made between the idea of a Canon and the fixing of the Canon, one has to prove that at one period the books which were subsequently admitted into the Canon were, as we have said, distinguished in degree but not in kind from the mass of sacred literature. The evidence of Ben-Sira, and of his grandson, is to the effect that no fixed Canon of Scripture, as we understand it, existed at about B.C. 100, and yet we know that at that time a large mass of literature was in existence of which certain books were held in high honour. The assumption is, therefore, justified that such books as Ecclesiasticus, Tobit, Judith, 1 Maccabees and others came under the same category as many other books, some of which were later included in the Canon, and the possibility existed of such books as those just mentioned being also included in the Canon. The definite formation of the Hebrew Canon is another question; concerning this, we have the evidence of the Mishna that it was not completed at the beginning of the Christian era. On the other hand, the evidence of Josephus shows that the final fixing of the Canon had taken place before the end of the first century A.D. The theory of Josephus, which was also that of the Rabbis, as to what constituted the claim to canonicity, was that a book must have been written within the “prophetical period,” i.e. from Moses to Ezra. This theory was not in accordance with facts, but it held the field nevertheless, and the Hebrew Canon was formed in accordance with it. The final official _imprimatur_ was in all likelihood given by the Jewish religious leaders at Jabneh. The final fixing of the Hebrew Canon was in all probability the work of the Pharisaic party. ADDITIONAL NOTE _The Conceptions underlying the Idea of Levitical Impurity._