Siman 197

Two who ate as one and a third arrived, and the two had already finished their meal, only they had not yet recited Birkat HaMazon and had not yet washed with mayim acharonim, and had not yet said "give us [wine] and we shall bless," the Tur wrote that he joins with them. And such is the wording of the Rosh (chapter seven, siman 18), and this is his wording: Therefore, two who ate and a third arrived, and he ate before the two said "give us and we shall bless" – he joins with them. Thus far his words. And it is clear from their wording that he joins without any condition. (For they explain in Berakhot 47a: If they were to bring me mushrooms..., would we not eat? That is to say: it is impossible that any person, even if he is satiated, would not find some food or other pleasant to him, and he would eat if they were to bring it to him.)

But the Rambam in chapter five, law 9, wrote: Two who were eating and finished their meal, and a third came and ate, if they are able to eat with him any amount, and even of other foods—he joins with them. Thus far his words. Behold, he wrote a condition: if they are able to eat with him. And this is more clarified in the Semag, who wrote: We estimate their mindset: if they did not eat so much that if they were to bring them types of delicacies and a beloved thing, they would still be able to eat—he joins. Thus far his words. Behold, it is explicit that if not—he does not join. And it is more explicit so in the Bahag, and this is his wording: And two who ate bread and finished their meal, and another person came and wants to join for zimun with them, we see if when they bring them something beloved to them from what they ate… and they do not eat—he does not join with them. And if they eat—he joins with them. Thus far his words. (And they interpret: "If they bring...", meaning: that they need to see that if they were to bring, if they would eat or not. And from the Bahag it is clarified that we require specifically from the foods they ate, unlike the opinion of the Rambam. And look closely and you will find it simple.)

According to this, our teacher, the Beit Yosef, wrote in section 1: Two who ate as one and finished, and a third arrived, in any case where if they were to bring him something he would be able to eat from it – he joins with them. And they are obligated to give him to eat so that he may join with them. And this is provided that he arrived before they said "bring us [water] and we shall bless." But if they said "bring us and we shall bless" and afterwards the third arrived – he does not join with them. Thus far his words. And behold, he wrote explicitly like the Rambam and not like the Tur. And so we hold, that the halacha follows the many, and the third does not always join except under the condition that has been explained. And I am wondered that the commentators did not remark that the Rishonim are divided on this. (And the Levush wrote from his own reasoning that it depends on a condition. And the Perishah took issue with him, that it does not depend on a condition, and in every case he joins, see there. And they did not see that the Rishonim disagree on this.)

Regarding that which our teacher, the Beit Yosef, wrote, that they are obligated to give him to eat so that he may join with them, we have already explained this in siman 193, section 6; see there. And regarding that which he wrote, that when they have said "bring [wine] to us and we shall bless" he does not join, our teacher, the Rema, wrote that the washing of mayim acharonim is equivalent to "bring to us and we shall bless." Thus far his words. And certainly mayim acharonim is more significant than "bring to us and we shall bless," for regarding "bring to us" there are those who disagree and hold that he does join (Magen Avraham, subsection 2, in the name of the Ran; and see in siman 179). Furthermore, "bring to us and we shall bless" only applies to a homeowner and not to a guest, whereas regarding mayim acharonim there is no distinction, as I wrote in siman 179. However, his intention is this: regarding "bring to us and we shall bless," it was explained there that if he wishes to recite a blessing over what he will eat, it is permitted. This is not the case with mayim acharonim, as I wrote there. For this reason he says that here, for the sake of joining for zimun, his law is like "bring to us and we shall bless," meaning: that they are able to recite a blessing and eat and join for zimun with the third (Magen Avraham, subsection 3). And there is one who wrote that it is a mitzvah to wash his hands and recite the blessing "Hamotzi" and eat a little (ibid. in the name of the Bach). And these are astonishing matters, and close to "gross eating" (Eliyah Rabbah). And we have never heard of anyone who would consider doing such a thing.

We say in the Gemara (48a) regarding ten who bless with the Name: Nine who ate grain, and one ate a vegetable—they join together to bless with the Name. And the same law applies when he drank a cup of wine (Tosafot), for drinking is included in eating and he can say "that we have eaten of His" (ibid.). And it is not specifically wine, for the same law applies to other beverages, except for water which has no importance at all, and joining together is not relevant to it. And even if he only dipped with them in brine—he joins. And specifically when he ate a kezayit of the vegetable or of another food, and drank a revit of wine or of other beverages or of brine. And likewise, specifically that he did not recite the final blessing, for after the final blessing it is not relevant that he should join. And they said in the Gemara there that it is not specifically one who joins, for the same law applies that three join. And so they said there: Seven who ate grain and three a vegetable—they join. But four do not join; even though the majority ate grain, nevertheless they do not join, for we require a majority that is very recognizable. And it is obvious that the one who blesses must be one of the bread eaters. And there is one who wishes to say that even water joins, because drinking is included in eating (Magen Avraham, subsection 6). And it appears that the primary view is like our teacher, the Beit Yosef, who ruled in section 2 that it does not join. And the reason: for we require in any event something that has some importance. And according to this, it is possible that prepared waters like seltzer, lemonade, or types of kvass—join. And so appears the primary view for the law.

The one who joins must recite an after-blessing over what he ate or drank. For Birkat HaMazon does not exempt the blessing of "Borei Nefashot" nor the blessing "Me'ein Shalosh." For Birkat HaMazon only exempts that which is within the meal. And even the diners themselves, regarding items brought after the meal—they require a blessing before them and after them, as I wrote in siman 177, and certainly those who did not eat at all in the meal, and whose joining is only for the zimun. Therefore, if they joined even by means of mezonot—they require a blessing for themselves. And they wait until the one reciting the blessing finishes the blessing of the zimun, according to what will be explained in siman 200, and then they recite the after-blessing. And there is one who wishes to say that Birkat HaMazon exempts wine and dates, because they nourish like bread (see Beit Yosef and Magen Avraham subsection 7). And this requires further study. Therefore, it is good that they intend not to fulfill their obligation through the blessing of the one reciting the blessing (ibid.).

The Rif and the Rambam wrote that specifically for ten they may join even with vegetables; but for three, only one who ate bread specifically may join. For in this matter, three is more stringent than ten, because with ten, since the primary zimun exists from those who ate bread, and this is only to add the mention of "our God," since they ate something, the Divine Presence rests and he can say "our God." But for the primary zimun, those who ate bread specifically are required, for so we learned in the Mishnah: "Three who ate," meaning: in a meal. And there is no meal except with bread. And even though it is taught in the Yerushalmi: two who ate grain and one vegetables – he joins; it is explicitly implied there that this is a minority opinion, and the sages disagree, see there. And behold, in the Rambam it is written explicitly: "a kezayit of bread." But in the Rif it says "a kezayit of grain," and therefore some say that it is not specifically bread, for even the blessing of mezonot suffices since it is grain (Kolbo). But the opinion of the Rosh and Ri is that even with vegetables it suffices, for since for ten he joins – all the more so for three. And behold, our teacher, the Beit Yosef, in his great work ruled like the Rambam, but in the Shulchan Aruch, section 3, he brought all three opinions. And because his opinion leans toward the ruling of the Rambam, he therefore wrote, and this is his wording: Therefore, two who ate and a third arrived, if they can obligate him to eat a kezayit of bread – it is better. And if he does not wish to – they should not give him to drink nor any other food. And if it happened that they gave him to drink or another food – they shall perform zimun with him, even though he does not wish to eat bread. Thus far his words. And he recanted from what he wrote in his great work, because Maharam of Rothenburg acted so as a practical ruling (ibid.). And the great Acharonim wrote that even ab initio one may do so, because the primary halachic ruling is like the words of the Rosh (Magen Avraham, subsection 9, and the Bach and Knesset HaGedolah).

It is a known matter that the Rambam in the fifth chapter, and the Tosafot and the Rosh and most of the poskim, hold that the obligation of birkat hamazon from the Torah is only when one has eaten to the point of satiety, and a kezayit is only midirabbanan. Except for the Ra'avad there, who holds that a kezayit is from the Torah. And there are those who hold that a kebeitzah is from the Torah, as I wrote in siman 184, see there. Therefore, a group that ate, where some ate to the point of satiety and others ate only a kezayit or a kebeitzah—it is proper ab initio that one of those who ate to the point of satiety should recite the blessing, and not one of those who ate a kezayit or a kebeitzah, for it is better that one obligated from the Torah should recite the blessing for one obligated only midirabbanan and not the reverse. However, ex post facto, or if there is no one among those who ate to the point of satiety who knows how to recite the blessing—one who ate a kezayit may recite the blessing, and everyone fulfills their obligation. And the reason is: since one is obligated to recite birkat hamazon, it is like the blessings over mitzvot where one can fulfill the obligation for his fellow even if he did not perform the mitzvah at all, based on the principle that "all Israel are guarantors for one another." And it is not similar to the blessings over pleasures, where one does not fulfill the obligation for another unless he also derives pleasure himself. Rather, regarding birkat hamazon, it is impossible to fulfill the obligation for others without eating at all, for how can he say "for we have eaten of His," when he has not eaten? Therefore, he must eat a kezayit. But when he has eaten a kezayit—it is sufficient, and he can fulfill the obligation for others (Tosafot 48).

Our teacher, the Rema, wrote in section 4: And some say that one is not obligated to bless by Torah law unless he drank and he desired to drink. And it is good to be careful ab initio if some of them drank and some of them did not drink—the one who drank should bless. Thus far his words. And this is its explanation: For there is one who is concerned for the words of Rabbi Meir who expounded "and you shall be satisfied"—this refers to drinking. And according to him, the obligation from the Torah is with a kezayit. But if he wants to drink and does not drink—the obligation is only rabbinic. Therefore, to be concerned for this opinion ab initio—it is proper that the one who drinks should bless; for if the one who did not drink blesses, perhaps he wants to drink and his obligation is only rabbinic. And if some of them ate to satiety and did not drink, and some of them ate a kezayit and drank—it is better that the one who ate to satiety should bless, because most poskim hold that satiety is a prerequisite by Torah law and not drinking (Magen Avraham subsection 12). And all this is ab initio, as in the previous law. But ex post facto it is not a prerequisite at all, as in the previous law. (And the Taz, subsection 4, understood that the intention of the Mordechai is even ex post facto, and wondered at this, see there. But his intention is not so, see there.)