A. Puncturing a pimple/boil on Shabbos:
Punctures it to let in air to heal it: One who breaks [open] a boil on Shabbos, if he does so in order to make for it an opening for air to enter through it to heal it, then he is liable for [the prohibition of] “Makeh Bepatish”.
The reason for this is: because he has fixed for it an opening, and anyone which fixes an opening in any item detached [from the ground] is liable for fixing a vessel, which is an offshoot of the “Makeh Bepatish” prohibition as explained in chapter 314 [Halacha 2]. And what difference does it make if one has fixed a vessel or fixed a wound, and thus also in the fixing of a hole in the wound contains the prohibition of “Makeh Bepatish”.
Now, although one is only liable on a hole made to enter and remove [something] thorough it as was explained there, [nevertheless here too one is liable] as this opening too is made to enter through it air and to constantly remove puss through it.
Punctures it to release the puss that is causing him pain: [However] if one breaks it open only in order to remove its puss which is causing him pain and not in order to enter air into it for purposes of healing, then it is permitted.
The reason: Now, although that one consequently creates a hole which is fit to [have something] entered and removed through it, nevertheless since he does not have a need for this, it is considered an action done not for its own use [which is not Biblically forbidden]. [Furthermore] even according to those opinions which say that an action which one does not do for its own use one is [also] liable on nevertheless here since the liability is due to fixing the wound thus if he does not care for this “fixing” and does not intend for it, then even though it consequently occurs [through him breaking open the boil], [nevertheless] this is not considered fixing at all and is as if he has done nothing. Albeit there does remain reason to decree against doing so due to that he may come to intend to make the hole [for healing, nevertheless] in a case of pain [the Sages] did not make such a decree.
Other Opinion: [However] there is an opinion which says that [the Sages] only permitted [breaking the boil] if one cares in doing so to merely remove its current puss and does not care if the boil will close back up. However if he desires that it remain open in this form in order for it to constantly remove its puss, then although he does not intend for air to enter through it [for healing] [nevertheless] it is forbidden.
The Final Ruling: It is proper to suspect for this latter opinion and to puncture the boil/pimple through a gentile [when done with intent to remain constantly open].
B. Scratching a pimple/boil on Shabbos:
However it is forbidden to scratch a boil [on Shabbos] as doing so removes blood and contains the prohibition of inflicting a wound.
The difference between scratching and puncturing: This is not similar to [puncturing it to remove puss] being that puss is not attached and absorbed within the skin and is rather as if it is deposited there within a vessel and upon opening the boil to remove [the puss] it is merely like one is opening a vessel to remove its content. This is opposed to blood which is attached and absorbed within the skin.
It may only be done if the following two conditions are fulfilled:
- Condition 1: When in pain it is permitted to be done in order to temporarily remove its puss and relieve the pain. However for it to permanently remain open and ooze puss is proper to only be done through a gentile. However to puncture it so it heal through having air enter into it is Biblically forbidden.
- Condition B: As well it is only permitted to be done if through doing one will not make a new wound that releases blood. However blood that is mixed with the puss does not pose a problem.
C. Cutting off a blister:
It is forbidden to cut a blister from one’s body whether with ones hand [or teeth] whether with a vessel, whether for himself, whether for others, whether it is [filled with] puss [blister], whether it is dry. And if one cut a puss [filled] blister with a vessel he is liable for shearing according to those which hold one liable for shearing even if he does not require that which is being sheared.
It is a Biblical prohibition according to some to cut it off with a vessel, whether it is a dry or mucus filled blister. It is Rabbinically forbidden to remove it with one’s hands [or teeth].
D. Removing a nail or pieces of skin from ones nail on Shabbos:
If majority of it has begun peeling off: A nail which is in the process of peeling off and cuticles, which are thin strings [of skin] which have [begun] separating off of the skin of the finger that surrounds the nail, if majority of it has peeled off then since they are close to becoming [completely] disconnected [therefore] there is no Biblical shearing prohibition applicable to it even when cut off with a vessel, although it is Rabbinically forbidden [to do so with a vessel].
Removing it with ones hands: However to remove it with ones hand, [being that it] is not the common way of shearing is permitted to do even initially if they are irritating him, so long as they have peeled off towards the top, meaning that it had began to peel off on the side of the nail [as opposed to under the nail].
Other Opinions: [However] there are opinions which say that towards the top means towards the body and not towards the nail.
The Final Ruling: One needs to suspect for both explanations [and thus it is never permitted to peel the skin off even when majority of it has begun to peel off] [Regarding the nail-See Q&A].
If only minority of the nail or skin has peeled off: If majority of [the skin or nail] did not peel off and one took it off with his hand then he is exempt [from Biblical liability] although has done a [Rabbinical] prohibition. [However] if one cut it with a vessel then he is liable for shearing. [Furthermore] even according to those opinions that say that an action which is not done for its own use one is not liable on, [nevertheless] there are opinions which say that by shearing one is liable according to everyone for the reason to be explained in chapter 340 [Halacha 2].
Summary-Removing a nail or pieces of skin from ones nail on Shabbos:
If they are not irritating him: Then it is forbidden in all cases to peel off a nail or skin.
If they are irritating him: Then regarding-
- Pieces of skin: Is forbidden to be removed whether with ones hands or with a vessel, even if it is irritating him and majority of it has peeled off. When done with a vessel and majority has not yet peeled off then it is Biblically forbidden due to shearing.
- A Nail: When done with a vessel and majority has not yet peeled off then it is Biblically forbidden due to shearing. If majority has peeled off then it is Rabbinically forbidden to remove it with a vessel. Regarding removing it by hand-see Q&A.
May one remove a nail which has peeled off in its majority?
Some Poskim rule that it is allowed to be removed by hand [or teeth] if they are irritating him, as the dispute with regards to what is considered going upwards and downwards was only with regards to pieces of skin and not with regards to the nail. Whatever the case one must beware that no blood is extracted in the process.
May one apply Vaseline to dry lips on Shabbos?
Vaseline may not be applied onto dry lips even if one will merely dab it on as opposed to smearing it, due to the healing prohibition. However it may be dabbed on fresh skin or lips for mere pleasure. It may not be smeared due to a possible smearing prohibition.
May one apply powder or a spray to feet with bad odor?
Some Poskim rule that one may not do so on Shabbos due to the healing prohibition, although one may mix it in water before Shabbos and then use it to wash ones feet in a way that appears that one is simply washing the feet.
If the powder has healing powers then it is forbidden [to be placed on feet which require healing according to all] due to the healing prohibition.
 Ketzos Hashulchan 143 in name of Mishneh Berurah.
 Rabeinu Tam. The former opinion is that of Rashi.
 Ketzos Hashulchan 143/1; Mishneh Berurah 99
 Halacha 37
 Piskeiy Teshuvos 328/25
 Ketzos Hashulchan 143/1 and footnote 3; Az Nidbaru
 So rules Peri Megadim M”Z 328/23, brought in Taharah Kihalacha 19/79-2, Upashut!
 Beir Moshe 1/36-4; 2/29-3
 See Beir Moshe [1/36-4] where he discusses the reasons for why it may even be smeared being that it is too soft of an item to contain the smearing prohibition as well as that its main intent is to be absorbed within the skin. However in his conclusion he rules not to be lenient to smear it and rather may only dab it. See also Beir Moshe 2/29-3.
Vetzaruch Iyun from Ketzos Hashulchan regarding if this really contains smearing. [See Misc laws of Shabbos” The laws of smearing]
 Ketzos Hashulchan chapter 138 footnote 31; Piskeiy Teshuvos 328/26
 Ketzos Hashulchan chapter 138 footnote 31; Kinyan Torah ; See also Beir Moshe 1/34
 See Piskeiy Teshuvos 328/26
 Beir Moshe 1/34; Piskeiy Teshuvos 328/26