Surely Yaakov trusted Yosef's promise. Why did he insist that Yosef swear?
Ramban and Seforno: So Yosef would be able to answer Pharaoh, should he refuse him permission to take Yaakov out of Egypt. 1
Ohr ha'Chayim: Refer to 47:31:152:1 and 47:31:152:2.
Ha'amek Davar: It is because Yosef did not want to make a Bris.
To whom did Yaakov bow?
Rashi (according to Sifsei Chachamim): To Yosef ("One bows before a fox, in its time" 1 ); and also to the Shechinah.
Seforno, Ha'amek Davar 2 : He bowed down in thanks to Hashem because of the good news, that Yosef had agreed to his request.
Rashbam: He bowed down to Yosef.
What is the significance of the fact that Yaakov bowed down "Al Rosh ha'Mitah"?
Rashi #1: Yaakov turned towards the Shechinah (for the Shechinah is to be found at the head of the bed of a sick person 1 - Shabbos 12b), and bowed down to it simultaneously.
Rashi #2: Yaakov bowed [to Hashem] because he saw that his bed was complete; i.e. (unlike his father and his grandfather,) all his children were righteous.
Rashbam: Yaakov bowed [to Yosef] from the head of the bed, where he was.
Ha'amek Davar: Yaakov bowed to the Shechinah, but did not want to appear to bow to Yosef; there was great adamancy that he had done so earlier (refer to 46:29:2:4 and the notes there). Therefore he turned his head to the side, to the head of the bed.
Gur Aryeh: How do we derive that this was Yaakov's intention? Since Yaakov was bowing before Hashem, he could have directed his bow to any direction, and the Torah need not have specified it. It tells us that he bowed towards the head of the bed, to teach that the Shechinah rests by the head of a sick person.
Hashem promised to return Yaakov to Eretz Yisrael (46:4). Why did he make Yosef swear?
Riva citing R. Tam of Orleans #1, Moshav Zekenim: Hashem's promise could be fulfilled through returning the bones. Yaakov wanted his body to be buried in Eretz Yisrael.
Riva citing R. Tam of Orleans #2: Hashem's promise could be fulfilled later. Yaakov wanted Yosef to take him immediately to Eretz Yisrael.
Why did Yaakov say "Hishava Li," "to me"?
Ohr ha'Chayim #1: The Shevu'ah will pacify and satisfy me.
Ohr ha'Chayim #2: Yaakov had a hidden reason.
Ohr ha'Chayim #3: Swear based on my intent, i.e. without stipulations that will enable you to nullify it.
Malbim: I will not make you swear, the way Avraham told Eliezer "v'Ashbi'acha" (24:3). That would look like you are forced. Rather, swear willingly, from your desire.
Ha'amek Davar: Take a Shevu'ah between man and Shamayim, but not like Avraham made his slave swear. One cannot force his son to swear Bal Korcho (against his will)!
QUESTIONS ON RASHI
Rashi writes: "One bows before a fox, in its time." If Yaakov thought it proper to bow before Yosef (as a ruler), why didn't he do so when he first saw him, immediately upon his arrival to Egypt (46:29)?
Gur Aryeh: It would have been disgraceful for Yosef for his own father to bow before him [in public]. 1 It would appear to be flattery by Yaakov, in order to obtain what he needed from Yosef. On this occasion, however, Yaakov bowed after Yosef had already sworn to oversee his burial.
Rashi writes: "From here we learn that the Shechinah rests above the head of a sick person." But Yaakov was not yet sick! (He fell sick only in the next verse (48:1).)
Gur Aryeh: Yaakov had already fallen weak, 1 as he was already instructing as to his passing and burial. The Shechinah rests upon the head of a weakened person as well.
Compare to Ramban (to 47:29).
Rashi writes: "The Shechinah rests above the head of a sick person." Why is this so?
Gur Aryeh: Hashem rests upon the downtrodden and lowly of spirit (Yeshayah 57:15).
Maharal #1 (Chidushei Agados Vol. 2, p. 19, to Nedarim 40a): The physical aspect (Chomer) of a person declines when he is sick; therefore Hashem (who is apart from anything physical) rests over him.
Maharal #2 (Netzach Yisrael Ch. 10, p. 64): An ill person diverges from the usual natural order, and needs special protection. That is why the Shechinah rests over his head.
Rashi writes: "Alternatively... [Yaakov bowed in gratitude] that there was no Rasha among his offspring... for Yosef, [despite his hardships,] remained righteous." Yosef had merely sworn to fulfill Yaakov's request; he had not yet done so!
Gur Aryeh: Yaakov had no doubt that Yosef would fulfil his oath.
Rashi writes: "[Yaakov] turned himself towards the Shechinah." If Yaakov was bowing before Hashem (and not before Yosef), where do we find a source for the parable of bowing even before a lesser person (see 47:31:2:1*)?
Mizrachi: If Yaakov bowed primarily to Hashem, the verse should have said explicitly, 'Yaakov bowed to Hashem.' Rather, he bowed to Yosef (but directed himself towards the location of the Shechinah).
Gur Aryeh: Yaakov could not be bowing to Hashem only now, in gratitude and relief, for allowing him to be buried in Eretz Yisrael. Hashem had already promised Yaakov directly, "I shall bring you back up" (46:4) [i.e. to Eretz Yisrael for burial]. Bowing now that Yosef had promised to carry it out would make it seem that he had doubted Hashem's promise. [Rather, he bowed to Yosef.]
