1. _The Pentateuch:_ Definition:--"The Pentateuch is the Greek name given to the five books--commonly called the Five Books of Moses. In the time of Ezra and Nehemiah it was called "the Law of Moses," or "the Book of the Law of Moses," or simply "the Book of Moses." This was beyond all reasonable doubt our existing pentateuch. The book which was discovered in the Temple in the reign of Josiah, and which is entitled "the Book of the Law of Jehovah by the hand of Moses," was substantially, it would seem, the same volume, though it may afterward have undergone some revision by Ezra. The present Jews, as we have already seen, usually call the whole by the name of Torah, i. e., "the Law," or Torath Mosheh, "the Law of Moses." (Smith's Old Testament History, p.. 654.) 2. _Greek Titles of the Books:_ "The division of the whole work into five parts was probably made by the Greek translators, for the titles of the several books are not of Hebrew, but of Greek origin. The Hebrew names are merely taken from the first words of each book, and in the first instance only designated particular sections, and not whole books." (Dr. Smith's Old Testament History, p. 654.) 3. _The Question of Authorship:_ "Till the middle of the last century (eighteenth) it was the general opinion of both Jews and Christians that the whole of the Pentateuch was written by Moses, with the exception of a few manifestly later additions--such as the thirty-fourth chapter of Deuteronomy, which gives the account of Moses' death. The first attempt to call in question the popular belief was made by Astruc, doctor and professor of medicine in the Royal College at Paris, and court physician to Louis XIV. He had observed that throughout the Book of Genesis, and as far as the sixth chapter of Exodus, traces were to be found of two original documents, each characterized by a distinct use of the names of God; the one by the name Elohim, and the other by the name Jehovah. Besides these two principal documents, he supposed Moses to have made use of ten others in the composition of the earlier part of his work. The path traced by Astruc has been followed by numerous German writers. * * * * * It is sufficient here to state that there is sufficient evidence for believing that the main bulk of the Pentateuch, at any rate, was written by Moses, though he probably availed himself of existing documents in the composition of the earlier part of the work. Some detached portions would appear to be of later origin; and when we remember how entirely during some periods of Jewish history, the Law seems to have been forgotten, and again how necessary it would be after the seventy years of exile to explain some of its archaisms, and to add here and there short notes to make it more intelligible to the people, nothing can be more natural than to suppose that such later additions were made by Ezra and Nehemiah." (Dr. Smith's Old Testament History, pp. 653-655.)