The Gemara (Shabbat 49a) says that tefillin must only be worn with a "guf naki" (clean body) which is defined by Abaye and Rava respectively as flatulence and sleeping. Other Rishonim, like the Maharam (Orchot Chayyim I Tefillin 3), and Achronim like Arukh Hashulchan (OC 38:6), and Chatam Sofer (Shabbat 49a) likewise include improper thoughts as a disqualification.

My question is, does anyone know of any responsa, psak, or halakha (with preference for more modern ones) that addresses situations that clarify the requirement of "guf naki" for men? Does anyone clarify if it is dirt, blood, or lack of bathing (weekly? monthy? less than standard?) that would qualify as non-"naki?" For example, does any posek deal with wearing tefillin on a camping trip when showering is infrequent and good hygiene is difficult? Or about wearing tefillin after a red-eye flight or all-nighter?

  • 1
    [Back then most people didn't have the opportunity to take shower each day.] Commented Dec 29, 2020 at 8:13
  • 1
    The satmar rebbe was against putting on t'fillin to non orthodox for this reason and wrote about it.
    – interested
    Commented Dec 29, 2020 at 9:24
  • 1
    I've never seen hygiene in the rules for guf naki.
    – N.T.
    Commented Dec 29, 2020 at 11:22
  • 1
    @N.T. See these related posts. judaism.stackexchange.com/q/61862/11105, judaism.stackexchange.com/q/61852/11105
    – SophArch
    Commented Dec 29, 2020 at 12:46
  • @Kazibácsi See here (torahmusings.com/2014/02/…) around notes 19-21 for sources that say that tefillin was a neglected mitzvah. my question is what, specifically, the concern was. It doesn't seem to be have dirt on you. Nobody mentions blood specifically. Nobody mentions a required shower frequency. etc.
    – SophArch
    Commented Dec 29, 2020 at 15:25

2 Answers 2


Rashi and Tosefot explain: That he's able to withhold himself from farting or sleeping. Tosefot: Lest he sleep and in turn fart.

IMHO this seems related to feces due to two reasons.

  1. If he can't hold from flatulence he probably has "one in the chamber" in the sense of the Rif below of ''tzoah bimkomo''.
  2. I was told the reason one can cover the tefilin and urinate but must remove (or displace) the tefilin to flatulate even though the gas will dissipate and leaves no liquid or solid is because at the moment of farting the sphincter is open thus his colon counts as one surface with his leg thus it's like he has tzoah on his leg.

Berakhot 16a Rif

The officer told them R' Pappa said, Feces in his place, it's forbidden to say Kriat Shema. Explanation: Feces at the sphincter is the same.


וקי"ל כרב הונא חדא דהוא רביה דרב חסדא ועוד דקא מקשינן מינה בפרק (דף ל.) אמר להם הממונה דאמר רב פפא צואה במקומה אסור לקרות ק"ש פירוש צואה בפי טבעת היכי דמי אי דנראית פשיטא ואי דלא נראית לא ניתנה תורה למלאכי השרת לא צריכא דיושב ונראית ועומד ואינה נראית ומאי שנא מצואה שעל בשרו דאיתמר צואה על בשרו או ידו מטונפת מבית הכסא רב הונא אמר מותר לקרוא ק"ש ומשני במקומה נפיש זוהמא שלא במקומה לא נפיש זוהמא מדקא מקשינן מינה שמעינן דהלכתא היא איתמר ריח רע שיש לו עיקר רב הונא אמר מרחיק ארבע אמות וקורא ק"ש ורב חסדא אמר מרחיק ארבע אמות ממקום שכלה הריח וקורא תניא כוותיה דרב חסדא לא יקרא אדם ק"ש לא כנגד ...

Some are more lenient, some stricter. They discuss is it inside or outside, is it exposed sitting but unexposed standing.

The BIH (add citation) comments on צואה במקומו and says you must wash with water after #2, taking special care to rub and rinse clean around the anus, and one cannot say brachot etc. without getting clean with water, and that it does not suffice what they do in the west where they wipe with paper.

It's not unusual to bring a bottle of water, and pour down one's back with the right hand while rubbing clean with the left hand.


The answer is no. Those are not mentioned as problems for guf naki. It is not related to hygiene.

  • 1
    @NT - this is a comment not an answer. For it to be an answer you would need to substantiate your claim with a source.
    – Dov
    Commented Dec 30, 2020 at 9:55
  • @dov There is no source to quote. The point is, guf naki and hygiene are not connected in any source.
    – N.T.
    Commented Dec 30, 2020 at 12:56
  • I mean, there are a bunch of sources that say women could have a guf naki if they were conscientious. What do you think they mean by the term?
    – SophArch
    Commented Dec 30, 2020 at 13:38
  • The same thing as for men, mainly flatulence and improper thoughts.
    – N.T.
    Commented Dec 31, 2020 at 21:29
  • 1
    So bring the source saying what the meaning of guf naki is, and you will have demonstrated (if not 100% conclusively) what it is not.
    – Mordechai
    Commented Dec 31, 2020 at 23:45

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .