Commento su Berakhot 6:8

מברך אחריהן שלש ברכות – Anything from the seven species, [after eating] one recites the three blessings [of ברכת המזון] as Rabban Gamaliel holds that [the words] “when you have eaten your fill, give thanks [to the LORD your God” (Deuteronomy 8:10), does not refer to bread alone, but to all seven of the species that are mentioned above in the portion of this verse (ibid., verse 8, “a land of wheat and barley, of vines, figs and pomegranates, a land of olive trees and honey”). And in this verse, the three blessings are hinted at: “give thanks” – this is the blessing for food; “for the…land” – this is the blessing of the Land (of Israel); “for the good [land which He has given you]” – [this is the blessing of] “who builds Jerusalem.” And similarly, he says, “that good hill country and the Lebanon” (Deuteronomy 3:25).

If one has eaten grapes, figs or pomegranates he blesses after them three blessings, the words of Rabban Gamaliel.
The sages say: one blessing which includes three.
Rabbi Akiva says: even if one ate only boiled vegetables and that is his meal, he says after it the three blessings.
If one drinks water to quench his thirst, he says “By Whose word all things exist.”
Rabbi Tarfon says: “Who creates many living things and their requirements.”
Until now the Mishnah has been discussing blessings recited before eating. This mishnah and the next chapter deal with the Birkat Hamazon, the blessing after food (I don’t really like the term, “Grace After Meals”). The concept of Birkat Hamazon is derived from Deuteronomy 8:10, “When you eat and you are satisfied you will bless the Lord your God.” Today the Birkat Hamazon contains four blessings, but the Mishnah refers to it as “three blessings” the fourth blessing was a later addition.
The full Birkat Hamazon, all three blessings, is recited only after eating certain foods or after eating a “meal”. After eating other foods which don’t constitute a “meal,” one blessing is recited. This one blessing includes the themes in the three blessings of the full Birkat Hamazon. In our mishnah there is a debate over when one recites the full version of the Birkat Hamazon and when one recites the abbreviated one blessing version.
Section one: According to Rabban Gamaliel the full Birkat Hamazon is recited over grapes, figs or pomegranates, all of which are among the seven species mentioned in Deuteronomy 8:8. This is the verse to which the blessing in verse 10 (see above in introduction) refers, and hence one recites the full Birkat Hamazon over these foods. Rabban Gamaliel would also hold that the full Birkat Hamazon is recited over the other foods that are referred to in the verse, including bread.
Section two: According to the sages, one recites an abbreviated version of the Birkat Hamazon over these foods. Today this blessing is called, “Brakhah Acharonah” the “last blessing.” One would recite the full Birkat Hamazon only over bread, because only bread constitutes a proper meal.
Section three: According to Rabbi Akiva what foods are eaten does not determine whether one recites a full or abbreviated Birkat Hamazon. Rather what is determinative is whether or not something constitutes a “meal” or a “snack.” If one eats boiled vegetables as one’s meal, then one says Birkat Hamazon. This would have many ramifications for today’s practice, where many people don’t necessarily eat bread with every meal. For instance, according to Rabbi Akiva, if one sat down for a meal of steak and potatoes, a hearty meal by most accounts, one would recite Birkat Hamazon afterwards, whereas according to the other sages in this mishnah, he would not.
Section four: The final section of this chapter returns to briefly discuss blessings recited before eating. Water was sometimes drunk to quench thirst, and sometimes drunk merely in order to help digest food. Our mishnah implies that if its function was just to clear the food from one’s throat, then no blessing is recited. In such a case water is not “food” and therefore no blessing is recited. However, if the function was to quench thirst, then the water counts as food and a blessing must be recited. The first opinion holds that the blessing recited is, “By Whose word all things exist,” the default blessing referred to above in mishnayot 2-3. Rabbi Tarfon says that a different blessing is recited, one which we today recite after eating foods over which we don’t recite a full Birkat Hamazon or even an abbreviated Birkat Hamazon. This blessing is generally called today “Bore Nefashot.”

וחכ"א ברכה אחת – [One blessing] that is an abstract of the three blessings; if he ate grapes, figs, pomegranate, olives or dates, he recites the blessing, “on the tree and on the fruit of tree and on the splendid good land, etc.” and concludes the blessing [with the words: Praised are You….] on the Land and on the fruit thereof.” And in the land of Israel, one concludes the blessing: “on the Land and on its fruit.” And this blessing itself he would recite, “on the wine,” but he would open [with the words]: [Praised are You….] on the wine and on the fruit of the vine” (see Berakhot 44a). And on ever thing that is made from the five kinds of grain (i.e., wheat, rye, barley, spelt and oats), he would substitute [the words] “for the sustenance and on the provision” for “on the tree and the fruit of the tree” and conclude [the blessing with the words, “Praised are You…] for the sustenance and on the provision.”

אפילו אכל שלק – [overboiled] vegetables and it is the meal that he depends upon [for nourishment, making a meal of it], he recites the three blessings of “when you have eaten your fill, [give thanks [to the LORD your God] (Deuteronomy 8:10), since it refers to what he has eaten. And the Halakha follows the Sages, that we do not recite the three blessings [of Birkat HaMazon] other than for bread , and on the seven species [of the Land of Israel], we recite the one blessing that is an abstract of the three [ברכה אחת מעין שלש] , but on all other things, we recite “בורא נפשות רבות וחסרונן/Who Creates Many Souls [who have] their Deficiencies/lacking”. And the explanation of the word, “חסרונן”/Deficiencies/that which they are lacking, such as bread and water where it is impossible to exist without them “on everything that [God] created for a living person to exist , that is to say, on everything in the world that also, had it not been created, human beings could exist and everyone was not create for pleasure and additional goodness and because there is this blessing, these two matters are covered in one long blessing that begins with “Praised [are You]” and concludes with “Praised [are You]” as it is found in the Jerusalem Talmud , “Praised are You, O LORD, eternal life of the universe.”

השותה מים לצמאו – Specifically [drinking water to quench one’s thirst], he recites the blessing, “For all things [that will be like God’s word]/שהכל נהיה בדברו".” But if one drinks water in order to swallow [i.e. wash down] some food that is stuck in his throat, he does not recite a blessing.

רבי טרפון אומר בורא נפשות רבות – He recites he blessing before drinking the water, but the Halakha does not follow Rabbi Tarphon, but rather, beforehand, recites “Shehakol” and afterwards, “בורא נפשות רבות”/Who Creates many souls.”