Seeing as Moshe being able to see the whole of Eretz Yisrael was in itself a miracle, why did he need to asend Har N'vo in order to see it?
Oznayim la'Torah: In order to minimize the miracle. 1
As is the way of Hashem. Refer to Bereishis, 6:14:1:2.
Seeing as the whole of Seifer Devarim was said in Arvos Mo'av, why does the Torah insert "me'Arvos Mo'av"?
Rashi: To inform us that Moshe made the ascent in one step - in spite of the many (twelve - Sotah, 13b) steps that led up to it.
Where was Har N'vo?
Sotah, 12b: It was in the territory of Reuven, as the Torah wrote at the end of Matos. This teaches us that Moshe died in the territory of Reuven. 1
Why did Moshe die in the territory of Reuven, and was buried in the territory of Gad?
Oznayim la'Torah (in Pasuk 6) #1: He died in the territory of Reuven (at the top of the mountain) beause that is where the vantage-point was from where he could see the whole of Eretz Yisrael before he died, 1 and he was buried in the territory of Gad because it faced Beis Pe'or. Refer to 34:6:3:1&2.
Oznayim la'Torah (in Pasuk 6) #2: See answer #2 as to why he was buried in the territory of Gad, and he died in the territory of Reuven, so that Hashem could accompany him to his burial-place, to teach us the Mitzvah of Halvayas ha'Meis.
See Oznayim la'Torah Ibid..
What are the implications of "Vayar'eihu Hashem es Kol ha'Aretz"? Why doews the Torah add the word "Kol"?
Rashi #1: Hashem showed Moshe the whole of Eretz Yisrael when it was at peace and the oppressors that were destined to tyrannize it (and the leaders who were destined to save it).
Rashi #2: Refer to Devarim 3:27:1:1.
Rashi #3 (in Divrei Hayamim 1, 25:5): If Hashem had not shown Moshe the entire land, he could not possibly have seen such distances on his own.
Targum Yonasan: And Hashem showed Moshe all the strong men of the land and the mighty deeds that they were destined to perform.
Hashem showed Moshe Gil'ad. Where was Gil'ad?
Ramban #1: Hashem showed Moshe the land west of the Yarden from Gil'ad, where Har N'vo - the section on which Moshe was currently standing - was situated, as far as Dan on the north-western border. 1
Ramban #2: Alternatively, Gil'ad was in the Levanon in Eretz Yisrael 2 - see Yirmiyah, 22:6.
Targum Yonasan: Hashem showed him Yiftach who came from Gil'ad.
Hashem showed Moshe Dan. What is the significance of "Dan"?
Rashi and Targum Yonasan: Hashem showed him (the tribe of Dan worshipping Avodah-Zarah, 1 and - Rashi) Shimshon who would descend from Dan, who saved them.
Ramban: Hashem showed Moshe the land west of the Yarden from Gil'ad, as far as Dan on the north-western border. 2
Beaing in mind that Moshe personally fought with Sichon and Og and captured their lands, why did Hashem now find it necessary to show him Gil'ad and Dan, which was part of the territory of Og?