In "E" Moses is commanded to smite with his rod, and the Nile will be turned into blood. In verse 17 _thine_ must have stood in the original and was altered to "mine" when the documents were pieced together.
In "P" Aaron is to take the rod, and now all the rivers of Egypt, and even the water in the houses, is to be turned into blood.
We have seen that the Exile produced two important prophetical works. The one is a vision of a restored Jewish state, contemplated under the guise of a Church rather than as a Nation; the work of the priestly Prophet Ezekiel. The other is incorporated in the second half of the prophecies ascribed to Isaiah; the author is unknown, but the work is an attempt to interpret the calamitous history of the Exile in such a fashion that the nation might be led to take as its ideal for the future, the Servant of Jehovah, the bearer of light to the nations of the world. The outlook in these two works is entirely different, yet both seem to have called forth a school which endeavoured to work out their ideals, but the school of Ezekiel obtained a more immediate recognition and exerted the greater influence on the nation. For the first time in Israel's history a prophet is found who is concerned with matters of ritual, the regulation of a priesthood, and the details of ecclesiasticism. Ezekiel endeavoured to secure the reforms demanded by the Prophets, not only by the effect of his own preaching, but by the formation of definite organisations and the establishment of certain customs. The priestly school which followed Ezekiel and developed his conceptions, possessed sufficient prestige to persuade the nation that their scheme was of Divine authority. Their work was carried on during and after the Exile, but with the exception of Ezra, the names of the authors have not been preserved. In the Bible history their work suddenly appears under the name of "the law of Moses" in 444 B.C. The first certain mention of the recognition and observance of this law is found in Nehemiah (viii.), where a memorable scene is described. Ezra the Scribe, "the writer of the words of the commandments of the Lord and of his statutes to Israel" (Ezra vii. 11), has come from Babylon, bringing with him the law of Moses. The people are gathered together on a certain day, and from morning to noon, the law is read in their hearing, with such comments and explanations as seemed necessary. The immediate result of this publication was the discovery that important provisions had been neglected and commands very seriously transgressed, and there followed such grief and alarm among those who listened, that it was difficult for the authorities to persuade the people to abandon their mourning and rejoice in the fact that the law had now been made known to them. On the morrow a further reading took place, when they discovered that on that very day they ought to be keeping a feast of tabernacles. The feast was therefore observed for the appointed time of eight days, and it is expressly noted that this had not been done since the time of Joshua. Other reforms were immediately set in motion; marriage with those not of pure Jewish blood was not only forbidden but, where such had actually been contracted, an immediate dissolution was enforced; a tax of one third of a shekel was levied for the upkeep of the Temple Services, and the law of the Sabbath was rigorously enforced. Now this picture was not written by a contemporary, and critics have found such difficulty in discovering the exact historical facts that considerable doubt has been aroused, not only concerning the historicity of this event, but even concerning the existence of Ezra himself. But it is certain that in the Fifth Century B.C., laws were obeyed and institutions were recognised, of which we have no record, outside the Pentateuch, in the earlier historical books. The question to be answered is: What was that "law of Moses" which Ezra brought to Jerusalem and read to the people? Later Judaism calls the first five books of the Bible "the Law of Moses," and for centuries both Jewish and Christian scholars have identified Ezra's law with these books, have supposed that they existed from the time of Moses downwards, but were entirely neglected by the Jews until this time. Modern research is compelled to dissent altogether from this tradition. Our purpose in this book prevents us from discussing the details of this controversy, but in addition to what has been already said in an earlier lecture, the main results of critical study on the origin of the Law may be outlined.