HESECH HA'DA'AS FROM EATING OR DRINKING [Seudah: Hesech ha'Da'as]
(Ravin): They enlarged the Mizbe'ach in order that the Shisim (a pit into which the Nesachim flowed) would be within (under) the Mizbe'ach.
They reasoned that drinking ('consumption' of Nesachim) should be like eating (Korbanos that are burned, i.e. within the boundaries of the Mizbe'ach).
Pesachim 103a: Rava blessed Borei Peri ha'Gafen on the first cup, and again on the cup of Birkas ha'Mazon and drank it.
Rav Yakov bar Aba: Granted, in the Reish Galusa's house we blessed a second time because we were unsure whether we will receive wine. Here, the cup is in front of us, and we plan to have it!
Rava: I did like Talmidim of Rav (after they accepted the words of Rav Yeiva):
Rav Yeiva the elder was serving Rav Beruna and Rav Chananel, Talmidim of Rav, at a meal. They told him 'Hav Lan u'Nevarech' (give us a cup of wine, and we will bless Birkas ha'Mazon).' They reconsidered and said 'give to us and we will drink.'
Rav Yeiva: Rav says that once you said that you will bless, you may no longer drink! This is because you decided not to drink any more.
Berachos 42a: Rav Papa and Rav Huna brei d'Rav Nasan were served more food after the meal. Rav Papa ate.
Bei Rav Huna: Don't you hold that after the meal, one may not eat?
Rav Papa: That is only if the bread was taken away.
Rava and R. Zeira ate at the Reish Galusa's house. After the serving tray was removed, more portions were sent to them. Rava ate, R. Zeira did not, and asked Rava why he ate.
Rava: We intend to eat more if the Reish Galusa will serve more to us (even after our tray was removed).
(Rav): If one normally anoints his hands with oil after eating, his meal does not end until he does so.
(Rav Kahana): We normally anoint with oil after eating, so our meal does not end before this.
The Halachah does not follow these teachings. Rather, it is like R. Chiya bar Ashi, who said that one must bless right after washing.
47a: Rav and Shmuel were eating. Rav Simi bar Chiya came, and ate quickly.
Rav: Do you want to join for a Zimun? We already finished!
Shmuel: If they would bring dessert, wouldn't we eat?! (He may join.)
48a: Yanai ha'Melech and his queen ate bread. They brought Shimon ben Shetach to bless for them, and gave the cup to him to bless.
Shimon ben Shetach: I cannot bless, for I did not eat anything!
He drank the cup. They gave him another cup, and he blessed (for everyone).
Rif (Pesachim 21a): Once they said that they will bless, they diverted their minds from drinking. Therefore, if they want to drink, they must bless Borei Peri ha'Gafen.
Ran (DH Itsar): Some say that after saying 'Hav Lan u'Nevarech', they may not eat before blessing Birkas ha'Mazon.
Rif (Berachos 30a): Taking away the bread does not forbid eating more. Rather, the Halachah follows R. Chiya bar Ashi, who said that Berachah must immediately follow Netilas Yadayim.
R. Yonah (Berachos 30a DH Ela): Once one decided not to eat more and said 'Hav Lan u'Nevarech', he may not drink wine before blessing. Bread is different. Even if he decided not to eat more and removed the table, as long as he did not wash Mayim Acharonim, he did not totally cease eating bread. After washing, he may not drink even with a Berachah. Since he washed, he must bless immediately.
Ran (Chulin Reish 29a): If one was eating and decided not to eat more, even if he finished and even if he removed (the bread or table), he may eat until Netilas Yadayim. This is because eating has Keva. Sometimes one sits for a small meal, and it becomes a big meal. Drinking has no Keva. Therefore, if he reconsidered, he must bless again. Once Rav's Talmidim said 'Hav Lan u'Nevarech', they surely diverted their minds from drinking, so they must bless Borei Peri ha'Gafen. Also the Ra'avad says so.
Beis Yosef (OC 179 DH v'Da'as): The Ran must explain that Rav's Talmidim were not fixed to eat, rather, to drink. Even though it says 'they were sitting at a meal', and 'Hav Lan u'Nevarech' connotes that they were eating, we can say that they ate a little in order to sweeten the drinking. Primarily, they were fixed to drink. It is better to explain that the Ran says that when they are fixed to eat, 'Hav Lan u'Nevarech' ends drinking and they may not drink, but they may eat. However, if no Berachah is needed for eating, it is unreasonable to require a Berachah for drinking. Since it is the same meal, (the law of) drinking depends on (that of) eating. Also R. Yonah distinguishes between eating and drinking.
Taz (179:2): To answer his question, I say that if he just wants to drink more, he must bless. If he wants to eat more, and this arouses him to drink, then we say that drinking follows eating (so he need not bless on the drink). I say that this is only regarding what people normally drink for enjoyment, even without thirst.
Rambam (Hilchos Berachos 4:7): If one decided not to eat or drink, and afterwards reconsidered to eat or drink, even though he did not change his place, he blesses again. If he did not decide (to stop eating or drinking), rather, he intended to eat or drink again, even if he paused the entire day, he need not bless again.
Rebuttal (Ra'avad): This was taught only regarding drinking, but not regarding eating. The only interruptions for eating are Mayim Acharonim or sleep.
Beis Yosef (DH veha'Rambam): The Rambam is astounding. Rav Papa answered that as long as they did not remove the food from the table, there was no Hesech ha'Da'as, and he may eat. Rashi explains like this. We concluded that this is not the Halachah. Rather, Berachah must be right after washing. This shows that even if he resolved not to eat more and removed the food, he may return to eat as long as he did not wash. Why does the Rambam forbid eating after he finished?! Perhaps the Rambam holds that in the episode with Rav's Talmidim, once he said 'Hav Lan u'Nevarech' they may not drink because they diverted their minds from eating and drinking. This shows that anyone who resolved not to eat may not eat. Rav Papa was eating in another's house. When he finished the food in front of him, they told him that he may not eat more, for presumably, when he saw that he finished and they did not bring more right away, he diverted his mind from the food, for he thought that they will not bring more. Therefore, when they brought more, they told him to bless. He answered that as long as they did not remove the bread and table in front of the guest, he has no Hesech ha'Da'as from eating, so he does not need another Berachah. In the case at the Reish Galusa's house, Rava said 'we rely on the plate of the Reish Galusa.' This shows that it depends on Hesech ha'Da'as of the eater. They argue about when people normally have Hesech ha'Da'as. Therefore, the Rambam wrote Stam 'when he resolved not to eat or drink more and afterwards reconsidered, he must bless again.' The Rambam's text did not say 'the Halachah does not follow these teachings', rather, 'this is not the Halachah. Rather, the Halachah is like R. Chiya bar Ashi.' Before this, the Gemara taught that one who normally anoints with oil before blessing may not bless before anointing. The Gemara said that the Halachah does not follow this. Rather, one blesses immediately after washing, without interrupting for oil.
Rosh (Berachos 6:31): As long as one did not wash for Birkas ha'Mazon, he may eat. According to Rashi and the Rashbam, saying 'Hav Lan u'Nevarech' is like washing. Some distinguish between eating and drinking. This is unreasonable.
Rashi (Chulin 86b DH Kivan d'Amar): Saying 'Hav Lan u'Nevarech' shows that he finished eating. He may not drink without a Berachah Rishonah, for it does not join with his first meal.
Tosfos (Pesachim 101b DH keshe'Hen): Our Gemara connotes that when there is Hesech ha'Da'as, one may not bless ha'Motzi. He must bless Birkas ha'Mazon. If so, when we say (103b) 'you may not drink', this means until blessing Birkas ha'Mazon. Berachos 42a connotes like this. If there were no need to bless Birkas ha'Mazon before eating more, why did R. Zeira refuse? However, we can say that they were brought another food with bread, and it was hard for him to wash again. The Rashbam and R. Chananel explain like this, that Rav Yeiva said 'you may not drink until blessing Borei Peri ha'Gafen.' This is primary, for in Chulin, we say that a waiter blesses on every slice. It does not seem that he blesses Birkas ha'Mazon.
Tosfos (Berachos 42a DH Atacha): If one forgot to eat the Afikoman, and said 'Hav Lan u'Nevarech', this is not Hesech ha'Da'as. We rely on Hash-m's plate. If the Ba'al ha'Bayis says 'Hav Lan u'Nevarech', all are forbidden to eat. If a guest says so, they are permitted, and even he may return and eat with his host.
Tosfos (42a DH Tekef): Once one washed Mayim Acharonim, he may not eat until he blesses. The same applies if he said 'Hav Lan u'Nevarech', even without washing.
Tosfos (47a DH Ilu): It seems that the Halachah follows Shmuel. However if they said 'Hav Lan u'Nevarech', they diverted their minds from eating, so a third does not join with them.
Gra (OC 179:1 DH v'Achilah): Tosfos holds that 'Hav Lan u'Nevarech' obligates Birkas ha'Mazon before eating, but the episode with Shimon ben Shetach shows that the primary opinion is that of R. Yonah. This answers the question of Tosfos in Pesachim. Al the Amora'im in our Sugya hold that removing (the bread) is like Netilas Yadayim. The Halachah does not follow them. Only Netilas Yadayim obligates Birkas ha'Mazon.
Shulchan Aruch (OC 179:1): If one finished his meal and washed Mayim Acharonim, he may not eat or drink before blessing Birkas ha'Mazon. If he said 'Hav Lan u'Nevarech', this is Hesech ha'Da'as, and he may not drink before blessing first on it (the drink). The Rosh holds that eating is like drinking. R. Yonah and the Ran hold that eating is different, and he need not bless again. Even if he ceased eating and removed the table, he may eat more without another Berachah. As long as he did not wash his hands, he did not totally cease eating.
Gra (DH Aval): R. Yonah derives from the fact that the Gemara mentioned Netilas Yadayim. This implies that 'Hav Lan u'Nevarech' does not forbid eating. Therefore, removing (the bread) does not help (to obligate a new Berachah before eating more), even though it helps for drinking. We say that the Halachah does not follow the above teachings, for they discuss eating. Shimon ben Shetach was able to join Yanai in a Zimun, even though they already said 'Hav Lan u'Nevarech'. Other Chachamim argued with him, but only because he only drank wine and did not eat bread.
Kaf ha'Chayim (2): L'Chatchilah, whether he said 'Hav Lan u'Nevarech' or washed Mayim Acharonim, he should not eat or drink more. If he must, he blesses a Berachah Rishonah. However, if he only said 'Hav Lan u'Nevarech' and now he wants to eat, he only thinks the Berachah.
Mishnah Berurah (7): Even though R. Yonah holds that removing the table is a bigger Hesech ha'Da'as than 'Hav Lan u'Nevarech', it does not help for eating.
Mishnah Berurah (9): Many Poskim hold like the Rosh, that 'Hav Lan u'Nevarech' is the end of the meal, and one may not even eat without a Berachah. The Mechaber brought only this opinion in Siman 197. Therefore, l'Chatchilah one should be careful not to eat after 'Hav Lan u'Nevarech'. One who must bless (ha'Motzi) in the middle of a meal must also wash (Mayim Rishonim). Since he had Hesech ha'Da'as, he ceased to guard his hands. However, he does not bless Al Netilas Yadayim.
Kaf ha'Chayim (7): R. Yonah holds that deciding not to eat more is like 'Hav Lan u'Nevarech', and one may not drink wine without a Berachah. Other drinks are permitted without a Berachah. The Rambam says that this obligates a Berachah Rishonah even for food, and Darchei Moshe says that Rashi and the Rashbam agree, so one should not eat or drink after resolving not to eat more.
Shulchan Aruch (197:1): If two were eating, and they said 'Hav Lan u'Nevarech', and a third came, he does not join with them for a Zimun.
Rema: Mayim Acharonim is like 'Hav Lan u'Nevarech'.