Hilchot Kippah

[Be-Ahavah U-Be-Emunah – Chukat 5771 – translated by R. Blumberg]

Why do Jewish men wear a Kippah (Shabbat 156b)? It is out of modesty (Rambam, Hilchot De’ot). The Taz suggests that nowadays it fulfills, “Do not follow non-Jewish practices” (Vayikra 18:3), and that it is legally forbidden to leave one’s head uncovered for even a moment (Taz 8:3). Most later authorities agreed with him. Accordingly, whoever lifts his Kippah to give his head some air should make certain that it remains at least slightly on his head (Leket Ha-Kemach).
How big must a Kippah be? It must cover the head, and as with everything else, “most” is as good as “all”. One should therefore cover at least most of his head, i.e., most of where the hair grows (Shut Ha-Elef Lecha Shlomo 3). If one’s Kippah is smaller than that, some permit it, assuming that it is readily visible from all sides (Shut Igrot Moshe 1:1 and Shut Yechaveh Da’at 4:1).
Does one need a Kippah when one sleeps? It’s not required, but wearing it then is a pious act (Mishnah Berurah 4:11).
During prayers, does a Kippah suffice? Whoever wears a hat must wear it during prayers as well, for he is then standing before the King. He must be dressed as respectfully as possible (Piskei Teshuvot). Yet if someone suffices with a Kippah all day long (i.e. doesn’t wear a hat), then he needn’t make a special effort to wear a hat during prayers.
What if someone cannot wear a Kippah? If someone cannot wear a Kippah, like a spy in enemy territory, he should cover his head with his sleeve to recite blessings. If he has no choice, he can cover his head with his hand (Mishnah Berurah 4:12).
A Little Boy - A little boy should be accustomed as much as possible to wearing a Kippah. The mother of Rav Nachman bar Yitzchak scrupulously covered his head even when he was an infant (Shabbat 156a. Mishna Berura 4:11). But one should not make the infant’s life difficult.
Sports - Even during ball games or running, one needs a Kippah. If it flies off, one should obtain a hat that remains secure.
The Army - In the army, as well, one needs a head covering, even during training, and even during combat. Bar Kochba’s soldiers had their Tefillin on, but as for our humble selves, we can suffice with covering our heads.
Is one allowed to wear a Kippah made of netting with holes in it? The majority has to be fabric and not holes.
Is one allowed to have Biblical verses embroidered on the Kippah, or utterances about the Messiah? One is forbidden to enter a restroom with a verse or part of a verse or utterances from the Torah. And in general, as with any other piece of clothing, the Kippah should be modest and should not draw attention.
Is one allowed to have advertisements on a Kippah, such as about soft-drinks or
shoes? As noted, a Kippah has to be modest and should not draw attention.
Pictures - For the same reason, one should not put a picture on a Kippah.
Must a Kippah be circular, or can it be square or hexagonal? As noted, a Kippah should be normal and not strange, attracting attention.
May one wear Kippot of other religions such as Islam, Christianity or those of the Far East? No. That constitutes following the practices of the non-Jews. Likewise, a keffiyeh is forbidden.
May one replace a Kippah with a thick ribbon, but empty in the middle? No. As above.
Is there any virtue to having a black Kippah over any other color? Yes. Because that’s what people customarily wore in previous generations, but legally other colors are also possible.
When one has no Kippah, can one recite blessings under an umbrella? No. A Kippah has to be attached to the head. Better one should use his sleeve.
If one is committing a sin, like going to a forbidden entertainment spot, must he remove his Kippah so as not to profane G-d’s name? No. His Kippah proclaims that he fundamentally believes in and fears G-d even if he is sinning.
If one’s Kippah fell off in the middle of the Shemoneh Esreh, what should one do?
He should walk over and pick it up. Necessary walking is not considered an interruption.
If someone recites a blessing or prays without a Kippah, should he repeat the prayer or blessing? The Rabbis differ on that. He should not.
If someone is afraid to go among non-Jews wearing a Kippah, must he do so anyway? No. But he should wear a hat that does not identify him as Jewish.
Must one ask a non-observant guest to put on a Kippah? No. He and his way of life should be treated respectfully. A young man visited Rabbenu Ha-Rav Tzvi Yehuda Kook wearing a Kippah.
Rabbenu asked him why he was wearing it, and he replied: “Out of respect for you.” Ha-Rav Tzvi Yehuda asked, “When I visit you, must I take my Kippah off out of respect for you??”
If a Kippah falls down, must one kiss it upon picking it up? No. It’s not a holy object.
Must a tattered Kippah be placed in a Geniza? No, as above.
Is there any importance to wearing a larger Kippah during prayer? Yes. In prayer, one must conduct oneself as before a king. In prayer we must have reverence, so even if all day long one wears a Kippah improperly, in prayer one should wear it properly.
Does an unmarried female require a Kippah? Such is not the practice. It’s true that a Kippah is part of showing reverence, and a female must show such reverence as well, but she is exempt, just as she is exempt from many other mitzvoth. Maharal explains that this is because women have an easier time fostering reverence than men (even without the aid of a Kippah). And while there have been communities in which little girls wore Kippot when learning Torah (see Shut Yechave Da’at), that is not the practice either (see Shut Tzitz Eliezer).