Why did Pharaoh find it necessary to order Yosef to instruct his brothers to take wagons up to their children and wives, and fetch their father?
Ramban: Because knowing Yosef's honesty, Pharaoh suspected that, unless he commanded him to do so, he would not take anything 1 belonging to Pharaoh. 2
Seforno: So that his father would have no excuse to refuse. 3
Da'as Zekenim, Hadar Zekenim: The wagons were for the children and wives; but you should carry Yaakov on the shoulder - "va'Yis'u... Es Yaakov Avihem v'Es Tapam v'Es Nesheihem ba'Agalos" (46:5). 4
Ohr ha'Chayim: Refer to 45:17:151:1.
Malbim (to 45:17-19): It was a law of Egypt that the viceroy may accept strangers to live in Egypt temporarily, e.g. at a time of famine, but not to settle permanently. Only Pharaoh may do so. Sending wagons shows intent to settle in the land.
Ha'amek Davar (to 45:18): Pharaoh wanted Bnei Yisrael to come under his jurisdiction and settle in Egypt. He could not force them outright, for they were not from his land. However, he could command not to send grain to Eretz Kena'an, and they will need to come to Egypt during the famine. Their slaves and all their property would then remain in Eretz Kena'an until they return. There was food fitting for animals 5 and slaves in Eretz Yisrael (but no grain). Sending wagons would be the impetus for them to come willingly, bringing along all their possessions.
A reflection of Yosef's integrity, in spite of the vast wealth over which he had charge. (EC)
Ha'amek Davar - "Tzuveisah" implies unlike this. Also, Yosef sent more than Pharaoh authorized! (Refer to 45:19:1:6.)
Seforno: And indeed, it was when Yaakov saw the wagons that he decided to go and see Yosef (as the Torah records (45:27). Refer to 45:27:1:1, 45:27:1:4, 45:27:1:6.
The Trup for "Avihem" (46:5), Revi'i, suggests that what comes after is a new matter. (PF) Riva rejects this, for the verse ends "Asher Shalach Pharaoh Laseis Oso" (singular), i.e. to carry Yaakov!
The brothers said "Ein Mir'eh la'Tzon" (47:4)! Ha'amek Davar explained there that people are eating it. Perhaps Pharaoh heard that other food is growing, and he did not realize that people are eating it, and there will not remain enough for the animals. (PF)
QUESTIONS ON RASHI
Rashi writes: "'You have been commanded' - by my word." What is Rashi adding?
Gur Aryeh: I might have thought that Yosef "had been commanded" i.e. by someone else (and Pharaoh now told him to obey). Rather, Pharaoh was saying, "you are hereby commanded, by me."
Rashi writes: "You have been commanded - ... to say to them." What is Rashi adding?
Gur Aryeh: One does not command a person with the word "you," only to demand that someone else must do something! Rather, Yosef was commanded to say to his brothers to do the following.
Rashi writes: "'Do this' - This is what you shall tell them -- that it is with my permission." Why does Rashi explain this way?
Gur Aryeh: Pharaoh already told Yosef, "say to your brothers, do the following" (45:17); so what does this verse add? Pharaoh commanded Yosef to inform the brothers that he acted with Pharaoh's full consent.
