What was Hashem doing atop the ladder?
Rashi: He was guarding Yaakov. Why did Yaakov need protection? See footnote. 1
Tosfos ha'Shalem (8), from Bereishis Rabah (69:3): The angels saw that Yaakov's face resembled that on the Kisei ha'Kavod, and wanted to kill him, lest it look like there are two Powers. Hashem burned them. The Gur Aryeh and Oznayim la'Torah (to 28:12) explain that Yaakov needed guarding because the angels of Eretz Yisrael had already left, and those of Eretz Yisrael had not yet descended - Refer to 28:12:1.3:1 as to why this was so.
Hashem promised him and his children the land on which he was lying. That is not very much land!
Rashi: This teaches us that Hashem compressed the whole of Eretz Yisrael underneath him 1 - a sign that it would be as easy to conquer as four Amos [if they will deserve it].
Seforno: This promise refers to the entire region of Eretz Kena'an, where Yaakov was currently lying. It is an assurance that he would be a prince of G-d among the inhabitants of the Land, like Avraham and Yitzchak were.
Ha'amek Davar : The land that you are on now (Eretz Yisrael), which was promised to Avraham and Yitzchak, is for you, and not for Esav.
Tosfos ha'Shalem (5): What happened to the inhabitants at the time? Hashem made a place for them under the land - "umi'Tachas Zero'os Olam" (Devarim 33:27).
Tosfos ha'Shalem (15) citing the Tur: Hashem gave to him the place of the Mikdash, which is primary - automatically, the rest belongs to him.
Da'as Zekenim, Hadar Zekenim: This is like when they give a small land to great soldiers, and through their valiance they conquer all around it.
Why does it say "Avicha" regarding Avraham, and not Yitzchak? It is more appropriate for Yitzchak!
Hadar Zekenim, Riva: Avicha does not refer to Avraham, rather, to "Elokei." I am Elokei Avicha - Elokei Avraham, Elokei Yitzchak.
Moshav Zekenim, Tosfos ha'Shalem (2) citing R. Efrayim: Yaakov lived 15 years in Avraham's life. Avraham cherished him, and called him "my son." Yitzchak loved Esav more than Yaakov. 1
Tosfos ha'Shalem (5): Grandchildren are like children. Even the Brachos of Yitzchak were in the merit of Avraham.
Ohr ha'Chayim: This is to teach that Yaakov will inherit directly from Avraham; it will not go via Yitzchak. This eliminates any claim that Esav might have. 2 It is not needed to exclude Yishmael, who is a Shifchah's son; he belongs to Yitzchak. "Yerushah l'Esav Nasati Es Har Se'ir" (Devarim 2:5) - Esav's children received it for Esav, but Esav himself does not inherit Avraham.
Ha'amek Davar: Elokei Avraham hints to Hashgachah and protection from enemies. Elokei Yitzchak hints to Hashgachah for income. In Charan, Yaakov is in greater need of the former.
Oznayim la'Torah: It is an indication of a flaw in the relationship between Yitzchak and Yaakov (refer to 28:13:151:2*) on the one hand, and on the other of a lack of Kibud Av on the part of Yaakov, who abandoned his father for twenty-two years. 3
This is astounding. When Yitzchak realized that he blessed Yaakov by mistake, he said "Gam Baruch Yihyeh"! He saved Birkas Avraham and Eretz Yisrael to give them to Yaakov! Some say that Esav refused to be circumcised (refer to 25:25:1:2)! Perhaps they mean that Yitzchak showed more love to Esav, to try to draw him close (PF).
If this prophecy negates Esav's claim, it could equally have said that Yitzchak inherits Avraham, and Yaakov is Yitzchak's only heir! (PF)
Oznayim la'Torah: For which he was ultimately punished by being separated from Yosef for the same period of time - despite the fact that he went to Charan on the instructions of Yitzchak. See Oznayim la'Torah.
Why do we find that Hashem stood over Yaakov, but not over Avraham and Yitzchak?
Rosh (to Bereishis 42:1): The king does not stand over his field when it is plowed or seeded, only when the crops are piled up. Thus, Hashem told Avraham to go in the land (13:17), and "va'Yizra Yitzchak" (26:12) but it says about Yaakov, "Kodesh Yisrael La'Shem, Reishis Tevu'aso" (Yirmeyahu 2:3).
Malbim: The Torah says so to show one of the four ways 1 in which this was inferior to Moshe's prophecy. It seemed that Hashem was standing. 'Seeing' applies to prophets, who saw semblances - "va'Era... b'Kel Shakai" (Shemos 6:3) - Ispaklaryah she'Einah Me'irah. "U'Shmi Hashem Lo Noda'ti Lahem" - I did not give to the Avos knowledge of Me, i.e. Ispaklaryah ha'Me'irah.
Ohr ha'Chayim: The Avos are the Merkavah (Bereishis Rabah 47:6). Since Yaakov is the fourth 2 leg of the Merkavah (it is most appropriate to say so about him, for) he is the primary support.
Malbim (to 28:12): The others are - (a) Hashem spoke to Yaakov in a dream; (b) it was through riddles (the meaning of the ladder was not yet clear), and (c) it was through (i.e. he saw) angels.
Likutei Ha'aros on Ohr ha'Chayim (3): The Zohar (Vayechi) says that until David ha'Melech, Adam ha'Rishon was a leg of the Merkavah, therefore Yaakov was the fourth.
QUESTIONS ON RASHI
Rashi writes that Ha'Kadosh-Baruch-Hu does not attach His Name to Tzadikim during their lifetime. Why did Hashem say "Elokei Yitzchak," even though Yitzchak was still alive?
Rashi: The reason (that there is no guarantee that the greatest Tzadik will not still sin), was not applicable in the case of Yitzchak, who was blind and housebound. 1
Malbim (Torah Ohr 1): Through Avraham and Yitzchak, Hashem caused His Shechinah and Elokus to dwell in Eretz Yisrael, therefore He will give it to Yaakov.
In which case he was considered like dead, devoid of the Yetzer-ha'Ra.
Rashi writes: "Hashem folded up the entire Land of Israel beneath Yaakov." How can this be explained on a deeper level?
Gur Aryeh: The Land measures 400 Parsa'os by 400 Parsa'os. 1 Conceptually, the root of the number 400 is 4 (and a person's physical space is defined as 4 Amos 2 ). Any entity in the world falls under the rubric of its conceptual root. 3
Gur Aryeh writes further that the question is in any case mistaken. Perhaps he is referring to what he writes in Maharal (Gevuros Hashem, second intro.) about the essence of miracles (ibid. p. 15). Any entity has two aspects, Teva and Nes (natural and miraculous); these are not contradictory. (EK)
Rashi writes: "Hashem folded up the entire Land of Israel beneath Yaakov." Why did Hashem do this for Yaakov specifically?
Maharal #1 (Chidushei Agados Vol. 4, p. 108, to Chulin 91b):[Of the Avos, only Yaakov did not have unworthy offspring; therefore, the Land was given over entirely into his possession.
Maharal #2 (ibid.): Yaakov's trait was Kedushah; 1 he was worthy of the entire holy Land.