1)
Why did he say not to take out of your houses on Shabbos?
1.
Radak (19): Do not take from your houses to outside the city. Within Yerushalayim is permitted, for it was not a Reshus ha'Rabim.
2.
Malbim: He commanded also about Karmelis (Chachamim forbade carrying there, even though it is not Reshus ha'Rabim). Shlomo decreed about Eruvin (to forbid carrying in a Karmelis, unless it is fixed via an Eruv.
2)
Why does it say "v'Chol Melachah"?
1.
Malbim: Even Melachah mid'Rabanan.
3)
How will you be Mekadesh Shabbos?
1.
Malbim: Via ceasing from Melachah, and contentment.
