Whether Deuteronomy was written by Moses or many years later , this fifth book of the Pentateuch “introduces into the Bible for the first time the concept of canon – a bounded accepted body of authoritative literature.  See for instance Deuteronomy 4:2 and Deuteronomy 13:1
Ye shall not add unto the word which I command you, neither shall ye diminish from it
לֹא תֹסִפוּ, עַל-הַדָּבָר אֲשֶׁר אָנֹכִי מְצַוֶּה אֶתְכֶם, וְלֹא תִגְרְעוּ
All this word which I command you, that shall ye observe to do; thou shalt not add thereto, nor diminish from it.
אֵת כָּל-הַדָּבָר, אֲשֶׁר אָנֹכִי מְצַוֶּה אֶתְכֶם–אֹתוֹ תִשְׁמְרוּ, לַעֲשׂוֹת: לֹא-תֹסֵף עָלָיו, וְלֹא תִגְרַע מִמֶּנּוּ
So when in Deuteronomy 30:12 we read:
It is not in heaven, that thou shouldest say: ‘Who shall go up for us to heaven, and bring it unto us, and make us to hear it, that we may do it?’
לֹא בַשָּׁמַיִם, הִוא: לֵאמֹר, מִי יַעֲלֶה-לָּנוּ הַשָּׁמַיְמָה וְיִקָּחֶהָ לָּנוּ, וְיַשְׁמִעֵנוּ אֹתָהּ, וְנַעֲשֶׂנָּה
We should not be surprised to find this interpreted as still another proclamation of closure:
Moses said to them, “Do not say, ‘Another Moses will arise and bring us another Torah from heaven,’ for I say to you, ‘It is not in heaven’ – no part of it remained in heaven. (Devarim Rabah 8:6)
If you’re familiar with this blog, you can guess that “closure” is not on my top-ten list. To the contrary, I embrace the contradictions and dueling dialectic inherent in our religion where faith is complimented by rejection and purity is informed by impurity (see especially neither/nor and  )
I believe that the Rabbis shared my disdain for closure and they voice their embrace of a living, growing, struggling and dynamic Torah in one of the most wonderful Aggadic stories in the Talmud.
The details of the oven are not important. Let’s just say that Rabbi Eliezer argued that the oven was not a utensil which needed purification before use and the Rabbis disagreed. It’s at this point that the fireworks of the preeminent Talmudic argument begin.
It is taught: On that day R. Eliezer brought forward every imaginable argument, but the Sages did not accept any of them. Finally he said to them: “If the Halakhah (religious law) is in accordance with me, let this carob tree prove it!” Sure enough the carob tree immediately uprooted itself and moved one hundred cubits, and some say 400 cubits, from its place. “No proof can be brought from a carob tree,” they retorted.
And again he said to them “If the Halakhah agrees with me, let the channel of water prove it!” Sure enough, the channel of water flowed backward. “No proof can be brought from a channel of water,” they rejoined.
Again he urged, “If the Halakhah agrees with me, let the walls of the house of study prove it!” Sure enough, the walls tilted as if to fall. But R. Joshua, rebuked the walls, saying, “When disciples of the wise are engaged in a halakhic dispute, what right have you to interfere?” Hence in deference to R. Joshua they did not fall and in deference to R. Eliezer they did not resume their upright position; they are still standing aslant.
Again R. Eliezer then said to the Sages, “If the Halakhah agrees with me, let it be proved from heaven.” Sure enough, a divine voice cried out, “Why do you dispute with R. Eliezer, with whom the Halakhah always agrees?”
But R. Joshua arose and exclaimed: ‘It is not in heaven.’ What did he mean by this? — Said R. Yermiah: That the Torah had already been given at Mount Sinai; we pay no attention to a Heavenly Voice, because Thou hast long since written in the Torah at Mount Sinai, After the majority must one incline.
Nathan met [the prophet] Elijah and asked him, “What did the Holy One do at that moment?” Elijah: “He laughed [with joy], saying, ‘My children have defeated Me, My children have defeated Me.'” 
The story actually continues and includes a tragic ending for Rabbi Eliezer  , but for our purposes, we stop here. It is an amazing story and not surprisingly many students of the Aggadic stories in the Talmud count it as a favorite… I’ve heard that it was even made into a dramatic play.
The story needs no commentary, but I should add that I first heard this story from Rabbi Shlomo Riskin who gave an alternative translation for God’s punch line: ‘My children have defeated Me”. ניצחוני בני the word ניצח means to win, but it’s root, נצח means eternity. According to Riskin, an alternative reading is “My children have immortalized Me, My children have immortalized Me”.
Daniel Boyarin in his essay Old Wine in New Bottles: Intertextuality and Midrash, sees in this story (and Midrash in general) an example of “recreating a new moment of “Oral Torah,” which is, at the same time, always a new and present text as well as a reading of the Written Torah. In literary terms, there is a tension between the meaning of the quoted text in its “original” context and in its present context. What is so striking (and strange) about midrash is its claim that the new context is implied by the old one, that the new meanings (Oral Torah) revealed by recontexting of pieces of the authoritative text, are a legitimate interpretation of the Written Torah itself and indeed given with the very revelation thereof…”
So much for traditional midrash. According to Boyarin, this story goes one step further
“The point which has been missed is that R. Yehoshua’s “It is not in heaven” is an out of context citation. (ed. see above and the full text of Deuteronomy 30: 12 and what follows) R. Yehoshua is arguing with God from God’s own Text. You have given up Your right as Author and even as Divine Voice to interpret Your Torah when You said, “It is not in heaven.” But R. Yehoshua’s act is not only constative, describing or making a claim about interpretation, it is also performative, instituting and creating by its doing, the Oral Torah. For “it is not in heaven” is itself not in heaven. R. Yehoshua breaks it out of context and re-cites it in his own…
Without fanfare, R. Yehoshua uncovers radical new meaning in this verse, simply by reinscribing it in a new context. “It is not in heaven” does not mean only that the Torah is not beyond human reach but that it is beyond Divine reach, as it were. And God laughing with pleasure admits that R. Yehoshua, the faithful disciple, has indeed discovered a meaning which was given to Moses on Mt. Sinai, even though He Himself was not aware of it until now. “My children have defeated Me”; they have striven with Me and won. God laughed and, in that laugh, midrash was born.”
Boyarin points out that the unnecessary commentary on “it is not in heaven” based on the second text of “following the majority” is a late addition. R. Yermiah, its author, lived centuries later than the tannaitic protagonists of the story itself.
“Yermiah’s approach is tamer than the “original” meaning of R. Yehoshua’s statement, precisely because it does not involve the wresting of the Torah from Heaven in its very utterance, as his does. R. Yermiah talks about the absolute right of the interpreter to interpret; R. Yehoshua demonstrates how radical that right is. …. God’s assent to this radical act, His laugh of pleasure, establishes its legitimacy and thereby figures the regenerating and preserving function of the intertext.
Midrash is interpretation because it shows how meaning is created in the (nearly) infinite dialogical relations of text to text within the Torah and of the readers’ discourse to that of the Other.”
Both Boyarin and Riskin see in God’s response His pleasure in both the “disruptive” and “reconstructive” features of midrash. Ultimately this double movement of disruption and regeneration is precisely the raison d’etre and life-force in Jewish learning and future… and if God disagrees… it’s too bad, because the Torah is no longer in heaven..
 Deuteronomy – Devarim also known as Mishne Torah – the second or repetition of the Torah was, in the opinion of most Biblical scholars begun in the pre-exilic sixth century BC and finally edited in Exile by Ezra
 see The Five Books of Moses: Genesis, Exodus, Leviticus, Numbers, Deuteronomy by Everett Fox p 842
 “One of the most characteristic features of midrash is the way in which, as a reading practice, it violates the context of the texts being interpreted and cited. This is often cited as evidence for either the naiveté or hermeneutic bad faith -of the rabbis;’ Old Wine in New Bottles: Intertextuality and Midrash, Daniel Boyarin p542
 H.N. Bialik and Y.H. Ravnitzky, eds., Sefer Ha-Aggadah (The Book of Legends), translated by William G. Braude, Schocken Books, NY, 1992). page 223 Hebrew below:
אמר להם (רבי אליעזר): “אם הלכה כמותי חרוב זה יוכיח”. נעקר חרוב ממקומו מאה אמה… אמרו לו: “אין מביאין ראיה מן החרוב”. חזר ואמר להם: “אם הלכה כמותי אמת המים יוכיחו”. חזרו אמת המים לאחוריהם. אמרו לו: “אין מביאין ראיה מאמת המים”. חזר ואמר להם אם הלכה כמותי כותלי בית המדרש יוכיחו. הטו כותלי בית המדרש ליפול. גער בהם רבי יהושע אמר להם: “אם תלמידי חכמים מנצחים זה את זה בהלכה, אתם מה טיבכם?!” לא נפלו מפני כבודו של רבי יהושע ולא זקפו מפני כבודו של רבי אליעזר ועדיין מטים ועומדין. חזר ואמר להם: “אם הלכה כמותי – מן השמים יוכיחו”. יצאתה בת קול ואמרה: “מה לכם אצל רבי אליעזר שהלכה כמותו בכל מקום”. עמד רבי יהושע על רגליו ואמר: “לא בשמים היא”. [ציטוט מתוך דברים ל', י-יד: "...כִּי הַמִּצְוָה הַזֹּאת, אֲשֶׁר אָנֹכִי מְצַוְּךָ הַיּוֹם -- לֹא-נִפְלֵאת הִוא מִמְּךָ, וְלֹא רְחֹקָה הִוא. לֹא בַשָּׁמַיִם, הִוא: ... כִּי-קָרוֹב אֵלֶיךָ הַדָּבָר, מְאֹד: בְּפִיךָ וּבִלְבָבְךָ, לַעֲשֹׂתוֹ."]. מאי לא בשמים היא ? [מה הפירוש: לא בשמים היא?] אמר רבי ירמיה: שכבר נתנה תורה מהר סיני, אין אנו משגיחין בבת קול, שכבר כתבת בהר סיני בתורה: “אחרי רבים להטות” [ציטוט מתוך שמות כ"ג, א-ג בהמשך מספרת הגמרא שאליהו הנביא נשאל מה אמר הקב"ה באותו זמן. סיפר אליהו כי האל "חייך ואמר ניצחוני בני, ניצחוני בני"]
 read in the original Baba Metzia 59b or read for example The Talmud Revisited: Tragedy and “The Oven of Aknai” By Janet Madden