What is this Pasuk coming to teach us that we cannot learn from the previous Pasuk (See Rashi there)?
Rashi #1: It teaches us that the prohibition is confined to treating the crops as an owner, but does not extend to eating them. 1
Rashi #2 (in Yoma, 86b and in Rosh Hashanah, 22a): It teaches us that one may eat Shemitah produce, but not waste it or commercialize it.
Provided one declares them Hefker. See Sifsei Chachamim.
What are the implications of the words "Shabbas ha'Aretz"?
Rashi: They imply that one may only eat from what is Hefker, 1 but not from what is guarded.
Ramban: The repose of the land mentioned earlier 2 , or the produce of the Shabbos year, shall be for you all as livelihood, for you, your servants, your animals and your Chayos.
Why does the Torah see fit to include the owner in the list?
Rashi: To teach us that the Heter to eat Shemitah produce extends to the wealthy owner. 1
Otherwise, having stated in Mishpatim, 23:11 "ve'Achlyu Evyonei Amecha", we would have thought that only the poor are allowed to eat it (See Sifsei Chachamim).
And who is meant by "Sechircha" and "Toshavcha"?