Tomorrow is the 9th of Av. Because this date falls on Shabbat, the observance of the fast is postponed. The only fast that supersedes Shabbat is Yom Kippur; all the rest are delayed because of the superior sanctity of Shabbat.Since the rabbis considered Deuteronomy to be a collection of rebukes to Israel for their misdeeds that brought about punishment, it is particularly appropriate that this year we actually begin the reading of the book of Deuteronomy – D’varim – on the 9 Av. In the early midrashic work Sifre Deuteronomy the sages interpret the very word d’varim (words) in the first verse as “…they were words of rebuke… Moses gathered all of them together, from the oldest to the youngest, and said to them, ‘I am about to rebuke you. If anyone has anything to say in rebuttal, come forward and speak!’” The sages then interpreted the list of places that follows in verse 1:1 not as places where Moses spoke to them but as places where they had sinned, for which he now rebuked them. Similarly, the emphasis on 9 Av has always been not on what we suffered, but on what we did that brought about the suffering.The Book of Deuteronomy, however, is not only about rebuke. It is also about reconciliation, about God’s willingness to forgive Israel. It may begin with rebuke, but it concludes with “And this is the blessing...” (Deuteronomy 33:1.) Deuteronomy is a unique book. It is the only one of the five books of the Torah that identifies its author. It presents itself as a record of speeches made by Moses to the Israelites as they prepare to cross over into Canaan. It is his farewell oration, since he will not accompany them there. There is something ironic about the fact that Moses, who had said to God, “I am not a man of words – d’varim…” (Exodus 4:10) – now recites the words – d’varim – that make up the entire book of D’varim, Deuteronomy, surely one of the longest series of speeches in history.The ancient name for Deuteronomy was Mishne Torah (Repetition of the Torah), which is the source of the Latin name Deuteronomy. Moses goes over the events already recorded in previous books. He reviews what happened to Israel during these years of his leadership. He also repeats some laws and adds others that are new. He does indeed rebuke the people, but he also encourages them to remain true to the teachings about God that he has given them and to observe the commandments that they received when they enter their new land. At the end, he gives them his blessing.Biblical scholars today identify Deuteronomy as the scroll found in the Temple by the High Priest Hilkiah in the 18th year of the reign of King Josiah. This event is described in II Kings 22. The king was dismayed because it contained things that had not been observed since they were not found in any of the other holy scrolls that were known. He had the scroll read to all the inhabitants of Jerusalem and conducted a solemn ceremony of acceptance of its words and commands, followed by actions to put into practice the words of the book.The main actions he took were to destroy any places of idolatrous worship and to abolish all the shrines and altars to the Lord aside from the Temple in Jerusalem, totally centralizing the cult in that city. The laws of Deuteronomy allow for only one sacrificial site. Such a demand is found nowhere else and therefore required many changes in the way in which rituals were to be carried out. The reason for this change is not stated clearly, but it has been surmised that it was another step forward in purifying monotheistic belief, since a plethora of altars could more easily allow for deviations from pure monotheism, introducing pagan ways and even allowing for fetishistic practices.Deuteronomy presents a concept of God and of worship that is humanistic, devoid of magic and less anthropomorphic than that in other books. It is also in Deuteronomy that we find the two sections of the recitation of the Sh’ma commanding us not only to obey God, but to love the Lord in all ways, thus establishing for all time a unique relationship between God and Israel. In retelling the story of their journey from Egypt, Moses does not start at the beginning.He begins instead with a retelling of the story of the spies and the calamitous result of their negative report. As the Israelites stand ready to enter the land, he reminds them that had they listened to God and not been afraid, they would have been at this spot some 40 years earlier. Not only that, but Moses himself might then have been able to cross over the Jordan with them (Deut.1:37)! Perhaps this is his way of warning them that they must not repeat their rebelliousness as they enter the land, lest they be punished yet again. The people to whom he speaks now are not those who rebelled then. They have all perished. This new generation has a chance to be different and not to repeat the errors of the past.This was the same message that King Josiah intended to convey to his people when he had Deuteronomy read to them. Obedience to God that comes from love will bring them peace and prosperity. Disobedience will lead to calamity. Unfortunately it was not long after that that the Babylonians came and destroyed the Temple and sent the people into exile, the event that we commemorate on the 9th of Av. Had the people heeded the teachings of the book of Deuteronomy, abandoned their fetishistic practices and devoted themselves to the pure love of the Lord and His ways, perhaps the catastrophe could have been avoided.It is a message that we should remember when we observe the fast this Saturday night. The writer is a past president of the International Rabbinical Assembly and a two-time winner of the National Book Award. His most recent book is Akiva: Life, Legend, Legacy (JPS).