Talmud - Shabbat 109a שבת ק״ט א׳

that is placed into a barrel of beer should be severed because the beer will not ferment. A hand that frequently touches the eye causes blindness. A hand that frequently touches the ear causes deafness. A hand that touches the nose or mouth causes polyps [polypus]. It was taught in a baraita that Rabbi Natan says: She is a liberated entity, this evil spirit that rests on one’s hands before they are washed in the morning, and she refuses to leave until one washes his hands three times. Rabbi Yoḥanan said: When eye shadow is placed on the eyes it causes the evil spirit called the Daughter of the King to pass, and it stops tears and causes eyelashes to grow. That was also taught in a baraita: Rabbi Yosei says: Eye shadow causes the Daughter of the King to pass, and stops tears and causes eyelashes to grow.

And Mar Ukva said that Shmuel said: Leaves that are placed on the eye (Rabbeinu Ḥananel) contain no element of healing, and therefore one may place them on his eyes on Shabbat.
Rav Yosef said: Coriander contains no element of healing.
Rav Sheshet said: Hops contain no element of healing.
Rav Yosef said: Even for me, who is blind, coriander is harmful. He overstated coriander’s inefficacy, asserting that it is in fact harmful.
Rav Sheshet said: Arugula even for me, despite my blindness, is beneficial.
And Mar Ukva also said that Shmuel said: All types of hops may be eaten on Shabbat except for teruza, which is used exclusively for medicinal purposes.

Rav Ḥisda said: Melon juice, which is beneficial for the intestines, may be strained and drunk on Shabbat (ge’onim). The juice of pipuim, which are a type of vegetable (Rashba), may not be drunk on Shabbat. The Gemara relates: Ze’iri’s wife made melon juice for Ḥiyya bar Ashi and he did not consume it. She said to him: I made it for your Rabbi, Ze’iri, and he ate it, and you do not eat it? The Gemara explains: Ze’iri followed his own reasoning in permitting this drink, as Ze’iri said: One may place clear wine and clear water into a strainer used to strain dregs from wine on Shabbat without concern. Apparently, since the wine and water are drunk even with what little dregs may remain, one is doing nothing to improve them. Here, too, since melon juice is consumed this way, without being strained and for non-medical purposes, one is doing nothing and it is permitted.

And Mar Ukva also said: One whose hand or foot was wounded may immerse it in wine on Shabbat to stop the flow of blood, and he need not be concerned that he is violating the prohibition against healing on Shabbat. A dilemma was raised before the Sages: With regard to vinegar, what is the ruling? May one immerse a wound in it? Rav Hillel said to Rav Ashi: When we were in Rav Kahana’s house they said that vinegar is not permitted, as it is considered actual medicine. Rava said: And these people from Meḥoza, since they are delicate, even wine heals them. Therefore, they may not immerse their wounds in wine.

The Gemara relates: Ravina happened to come to the house of Rav Ashi. He saw that a donkey stepped on the back of Rav Ashi’s foot, and Rav Ashi sat and immersed his foot in vinegar on Shabbat. Ravina said to Rav Ashi: Does the Master not hold according to that which Rav Hillel stated, that vinegar is not permitted? He said to him: The back of the hand and the back of the foot are different because their wounds are dangerous.

Some say that Ravina saw that Rav Ashi immersed his foot in wine. Ravina said to him: Does the Master not hold according to that which Rava said: These people from Meḥoza, since they are delicate, even wine heals them? And the Master is also delicate. Rav Ashi said to him: The back of the hand and the back of the foot are different, as Rav Adda bar Mattana said that Rav said: A wound on the back of the hand or the back of the foot is like a fatal wound, and one may desecrate Shabbat for it.

The Sages taught in a baraita: On Shabbat, one may bathe in the therapeutic hot springs of the waters of Gerar, in the waters of Ḥamatan, in the waters of Asya, and in the waters of Tiberias; however, one may not bathe in the Great Sea, namely, the Mediterranean sea, nor in water in which flax was soaked, nor in the Sea of Sodom, because people bathe in those bodies of water only for medicinal purposes.

And the Gemara raises a contradiction based on that which was taught in another baraita: One may bathe in the waters of Tiberias on Shabbat and in the Great Sea; but one may not bathe in water in which flax was soaked, nor in the Sea of Sodom. This is difficult because in the first baraita the Sages prohibit bathing in the Great Sea, and in this baraita they permit bathing in the Great Sea.

Rabbi Yoḥanan said: This is not difficult, because this baraita, which permits bathing in the Great Sea, is in accordance with the opinion of Rabbi Meir, who deems all seas equal. That baraita, which prohibits bathing there, is in accordance with the opinion of Rabbi Yehuda, who holds that the Great Sea is unlike other seas. As we learned in a mishna: All seas purify like a ritual bath [mikve], as it is stated: “And God called the dry land earth, and the gathering together of the waters [mikve] He called seas” (Genesis 1:10); this is the statement of Rabbi Meir. Rabbi Yehuda says: Only the Great Sea purifies like a ritual bath, and the verse states seas only because there are many seas in the Great Sea, not because all seas purify.

Rabbi Yosei says: All seas purify like a ritual bath. They actually purify even more than a ritual bath, as they purify even when they are flowing. Immersion in a sea is purifying not only when its waters are still, but even when they are flowing. That is not the case with a ritual bath, whose waters only purify when still. And sea water is invalid for purifying zavim and lepers and for sanctifying purification water to mix the ashes of the red heifer with it. Those cases require spring water. Rav Naḥman bar Yitzḥak strongly objects to this explanation:

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

Shabbat 109a explores superstitions about harmful hand habits, ritual handwashing against evil spirits, and which foods or remedies are permitted on Shabbat.