What are the connotations of "v'Achalta v'Savata u'Verachta ... "?
Rashi (in Brachos, 15a) and Ramban (citing Brachos, 58b): It presents the Mitzvas Asei 1 of Birkas ha'Mazon after 2 eating bread (to bless Hashem for the satiating food and for the good land 3 that He gave you as an everlasting inheritance - Ramban).
Ramban: 'When you remember the slavery in Egypt and the affliction of the desert, and when you eat and are satiated in the good land, you will bless Hashem on it.
Seforno: 'To remind you that all the above-mentioned things that you received from Hashem'. 4
What are the implications of the word "v'Savata"?
Brachos 20b: The Torah obligates Birkas ha'Mazon only if one is satiated. Chachamim decreed even after eating a k'Zayis or a k'Beitzah of bread (according to R. Meir and R. Yehudah, respectively). .
R. Meir (Brachos 49b): V'Savata is drinking. (The Torah obligats Birkas ha'Mazon only if he also drank enough, so he is not thirsty.)
What was Birkas ha'Mazon before Yisrael entered the land?
Rosh (Bamidbar 34:2): They said only the first Brachah, ha'Zan Es ha'Kol. After they entered, they blessed also on the land. After the Churban of Yerushalayim, they added Bonei Yerushalayim. After those killed in Beitar were able to be buried, they added ha'Tov veha'Metiv - ha'Tov that the bodies did not decay all those years, and ha'Metiv, that they were able to bury them. The dearest Brachah is Al ha'Aretz v'Al ha'Mazon. If one did not mention in Birkas ha'Mazon Eretz Chemdah, Bris, Torah, life and food, he was not Yotzei.