Shabbat 151B

שימתין. קושרין את הלחי, לא שיעלה, אלא שלא יוסיף. וכן קורה שנשברה ⁠— סומכין אותה בספסל או בארוכות המטה, לא שתעלה, אלא שלא תוסיף.

to delay its decomposition. Similarly, one may tie the jaw of a corpse that is in the process of opening. One may not move it directly so that it will rise back to its original position, but so that it will not continue to open. And similarly, if one has a roof beam that has broken on Shabbat, one may support it with a bench or with long poles from a bed. One may not move it so that the beam will rise back to its original place, but so that it will not continue to fall.

גמ׳ והאמר רב יהודה אמר שמואל: מעשה בתלמידו של רבי מאיר שנכנס אחריו לבית המרחץ, ביקש להדיח קרקע, אמר לו: אין מדיחין. לסוך קרקע, אמר לו: אין סכין. קרקע בקרקע ⁠— מחלפא, מת בקרקע ⁠— לא מיחלף.

Talmud: The Talmud questions the Mishnah’s lenient ruling with regard to smearing oil on a corpse: But didn’t Rav Yehuda say that Shmuel said: There was an incident with a student of R' Meir who followed him into the bathhouse on Shabbat. The student wanted to rinse the ground. R' Meir said to him: One may not rinse on Shabbat. The student wanted to smear the ground with oil. R' Meir said to him: One may not smear on Shabbat. This indicates that it is prohibited to rinse or smear anything that may not be moved on Shabbat. The Talmud responds: The ground in one place can be confused with the ground in another place, and the rabbis therefore prohibited these activities even on a tiled floor, such as that of a bathhouse, due to a concern that one may come to do so on a dirt floor and smooth it out. However, a corpse cannot be confused with the ground, and it is therefore permitted to rinse a corpse and smear it with oil.