Question

If it is not too much trouble, I would be happy to hear the Rabbi’s opinion on the following:
Wine (and they also discuss other things) consumed before the meal is exempted by Grace after Meals, because it stimulates the appetite for the meal and is therefore considered part of it. But Tosafot in Pesachim (100a) wrote: “Therefore, if he recited a blessing over the wine before the meal and intended to drink during the meal, he does not need to recite afterward over it ‘for the vine’ [the concluding blessing]”—and their intention is a different reason for exempting the after-blessing on wine drunk before the meal (this seems to emerge from the Vilna Gaon’s explanation in section 174, that Tosafot disagreed with the reason that it stimulates the appetite, though this still requires further analysis): if one drinks wine during the meal [which of course is exempted by Grace after Meals], then since the blessing on the wine before the meal exempts the wine during the meal [from the blessing “who creates the fruit of the vine”], they are considered one long act of drinking, and Grace after Meals exempts them. But their reasoning needs to be understood: what difference does it make that halakhically there is a blessing that exempts it, when in practical reality we are talking about the meal?
• Because of a dispute among the medieval authorities (Rishonim) whether one recites a blessing over drinks during the meal, halakhic authorities wrote that in order to avoid doubt, one should drink and recite a blessing close to the meal and thereby exempt the drinks during the meal. And the Magen Avraham warned not to drink a revi’it, because then there would be a doubt regarding the after-blessing. [I will not go into here the nullification of the first blessing by the after-blessing.] According to the above principle of Tosafot, since according to the view that foods exempt drinks, the drink before the meal does not exempt the drink during the meal, it follows that according to that view Grace after Meals will not exempt the drink before the meal, and therefore according to that view one should recite an after-blessing. And so the Mishnah Berurah taught there as well—not to drink.
• Now, as stated, the reasoning of Tosafot is unclear. It seems that it can be explained in two ways. A. Something along the lines of “the prohibition gives it significance”; that is to say, since it is the same blessing, people perceive it as one joint eating. (And we find something in this spirit in the definitions of a meal, regarding someone who eats an olive-bulk of bread without formally establishing a meal—on the Sabbath, where he certainly can do so.) But the reasoning of “the prohibition gives it significance” is problematic, and it is hard to decide where to apply it. B. More likely, Tosafot mean that the reason a blessing on one thing exempts another thing is that this is defined as one act of eating, a kind of meal. [And therefore there can be an interruption here, for example if one leaves the house, etc., which is not an interruption for the blessing to take effect, since it has already taken effect.] Consequently, when one recites a blessing on a drink that exempts a drink during the meal, there is here one act of eating/drinking—one big, long meal.
• But according to this, why must it actually exempt the blessing in practice? Seemingly, even if one ate porridge before the meal, he should not need to recite an after-blessing, even though it does not exempt the porridge eaten during the meal, which is exempted by the food. To this one must answer that since it is difficult to pin down the exact parameters of a meal, while there are clear legal parameters in the laws of blessings that indicate, as stated, that this is one long meal, they established the rule specifically on that basis.
• Up to this point, this is a new straightforward explanation of the rule formulated by Tosafot.
• And according to this, I return to one who drinks before the meal in order to exempt the drinks during the meal: there is room to say that even if he drinks a revi’it, according to all views he should not recite an after-blessing, contrary to what the Magen Avraham wrote. That is because in practice the blessing exempts the drink by virtue of the rule of doubt concerning blessings, and according to my explanation of Tosafot that itself is enough, because it shows that this is one long meal. I would add that if the rule regarding doubt in blessings had been stringent, and one had to recite the blessing out of doubt, it would seem reasonable to say that for my purposes here it makes no difference whether the obligation to bless is out of doubt or certainty. And it seems that even though the rule is lenient in cases of doubt concerning blessings, the very halakhic change from a state of doubt to definite exemption is enough to define this as one long meal.