Shabbat 26A

לימא מר: מפני שהוא עף. חדא ועוד קאמר: חדא ⁠— מפני שהוא עף. ועוד ⁠— גזירה שמא יסתפק ממנו.

Let the Master say a different reason: Because tar is volatile, i.e., it is liable to evaporate quickly and cause a fire. The Talmud answers: He stated one reason and another: One, because it is volatile and potentially dangerous; and, furthermore, due to a decree lest one take sap from it.

ההיא חמתא דהות סניא לה לכלתה, אמרה לה: זיל איקשיט במשחא דאפרסמא. אזלא איקשיט. כי אתא[י] אמרה לה: זיל איתלי שרגא. אזלא אתלא שרגא. אינפח בה נורא ואכלתה.

The Talmud relates: A mother-in-law who hated her daughter-in-law said to her: Go adorn yourself with balsam oil. She went and adorned herself. When she came, her mother-in-law said to her: Go light the lamp. She went and lit the lamp. She caught fire and was burned.

״ומדלת הארץ השאיר נבוזראדן רב טבחים לכורמים וליוגבים״. ״כורמים״⁠ — תני רב יוסף אלו מלקטי אפרסמון מעין גדי ועד רמתא. ״יוגבים״⁠ — אלו ציידי חלזון מסולמות של צור ועד חיפה.

Since balsam oil was discussed, the Talmud cites the verse: “But Nebuzaradan the captain of the guard left of the poorest of the land to be vinedressers and husbandmen” (Jeremiah 52:16). The Talmud explains the verse: With regard to vinedressers, Rav Yosef taught: These poorest of the land were the balsam collectors in the south of Eretz Yisrael, in the expanse from Ein Gedi to Ramata. And the husbandmen; these are the trappers of the snail [ḥilazon], from which the tekhelet dye is produced in the north of the country, in the area between the Promontory of Tyre and Ḥaifa. Only a small number of poor people could barely eke out a living from these tasks, which involved mere gathering.

תנו רבנן: אין מדליקין בטבל טמא בחול, ואין צריך לומר בשבת. כיוצא בו: אין מדליקין בנפט לבן בחול, ואין צריך לומר בשבת. בשלמא נפט לבן ⁠— מפני שהוא עף, אבל טבל טמא מאי טעמא?

A baraita states: One may not light with ritually impure untithed produce [tevel] during the week, and needless to say one may not light with it on Shabbat. On a similar note, one may not light with white naphtha during the week, and needless to say one may not light with it on Shabbat. Granted, with regard to white naphtha, its prohibition is understandable because it is volatile and potentially dangerous. However, with regard to ritually impure tevel, what is the reason that the rabbis prohibited lighting with it?