Wednesday, August 12, 2009

achila + seviya: the Torah obligation of birchas hamazon

The Minchas Chinuch (mitzvah 430) writes that the mitzvah of bentching min haTorah is obligatory only when there is "achalta v'savata", a formal halachic act of eating (achila) after which one is satiated. Halacha defines eating as consuming at least a k'zayis of food within the time span of achilas pras (the time it would take to eat a small loaf, which is at most 9 minutes according to some poskim, as little as 2 minutes according to others). Therefore, if one nibbles slowly at a meal, one may not be obligated min haTorah in bentching (MG"A O.C. 210). The Minchas Chinuch extends this chiddush further and wonders if only a k'zayis must be eaten in the timeframe of k'dei achilas pras, or one must eat to the point of satiation during that time frame.

R' Tzvi Pesach Frank (Shu"T Har Tzvi) does not quote the M.C., but clearly disagrees. He cites the words of the Rambam (Brachos 1:1):
מצות עשה מן התורה לברך אחר אכילת מזון, שנאמר "ואכלת, ושבעת--ובירכת את ה' אלוהיך" (דברים ח,י). ואינו חייב מן התורה, אלא אם שבע, שנאמר "ושבעת--ובירכת"
and notes that the only condition the Rambam says which must be met to be Biblically obligated in birchas hamazon is feeling satiated. The Rambam does not say "achal v'sava" -- he just says "sava". (I am not 100% convinced. The Rambam mentions "achilas mazon" at the opening of the halacha and perhaps he is simply adding that satiation is a condition that must be met on top of achila, not that satiation is the only condition that must be met.)

One interesting nafka minah between these views is the famous chakira of R' Akiva Eiger (O.C. 186) regarding a boy who has a big meal just before the night of his bar mitzvah and bentches. When the sun sets the boy instantly becomes bar mitzvah and now counts as a gadol. Must this boy now bentch again because of his experience of satiation as a gadol, or is his bentching as a katan sufficient to exempt from the mitzvah?

Aside from the question of whether the mitzvah performance of a katan counts towards a gadol's obligation, one also needs to factor into the debate the fact that the experience of seviya as a gadol is not accompanied by a formal act of achila done as a gadol. -- whether the seviya of a gadol caused by the achila of a katan is enough to warrant birchas hamazon may depend on whether you take R' Tzvi Pesach Frank or the Minchas Chinuch's position.


  1. The Chazon Ish on the sugya in Yuma regarding the manna discusses something similar; why we can still bench before the food is digested, the manna was digested instantly, etc.. You might want to look it up

  2. Anonymous12:01 AM

    Not Brisk,
    That might have to do with the fact that according to the urban or desert legends I was taught in school ;-) the manna supposedly tasted like whatever one wanted it to taste like, instant satiation or saturation i guess.

    Chaim B,
    How is R Frank citing the Rambam, disagreeing with the Minchas Chinuch's "wondering" and particularly his source, all three seem to be under the impression or at least wondering the same impression that in order to qualify for "birchas hamozon" one must be satiated from the food or grain vodka they were imbibing on, otherwise the thanking doesn't count in the same way......

    Especially if the Rambam is basing his must be satiated conclusion on the biblical passage of "veachalta vesavta uveiracta"

    How else is one supposed to feel satiated, in the context the Rambam is referring to ,(and the source he purporedly used) other than by eating as in "ve-achalta" which would have the same "eating" laws as the ones you cite for the Minchas Chinuch's understanding, (time span of achilas pras).

    Not sure what R Eiger's bar mizvah big bochur's big mcdinner at sunset meal has to do with anything other than the koton versus godol issue.

    Jaded Topaz

  3. Anonymous9:04 AM

    Chaim B,
    one quick question,
    you said
    "Halacha defines eating as consuming at least a k'zayis of food within the time span of achilas pras (the time it would take to eat a small loaf, which is at most 9 minutes according to some poskim, as little as 2 minutes according to others)."

    Do you have a source for this definition of "eating" as in "kezayis of food" and "time span of a achilas pras" in the halachic equivalent of "Black's Law Dictionary" ?

    I ask cuz I found the reference to "loaf" somewhat interesting.
    Particularly cuz I believe the Rambam is the one that recommended "bread" as the food of choice for that satiated feeling.... If I recall correctly.

    If Bread is the food of choice for that "satiated" feeling then logically that is probably the reason for the birchas hamozon on bread (similar concept can be found on washing for pizza as meal...) as opposed to snacking on saltines ...

    "mezonos bagels" might be a large misnomer then, as I'm not sure how that concept makes sense, halachically in the context. unless I don't understand the mezonos concept in the right way....

    Jaded Topaz