Parshas Acharei Mos tells us that we must cause suffering to ourselves on Yom Kippur. Nevertheless, the exact definition of “suffering” is unclear. In Gemarah Yoma, the Gemara suggests the perhaps it means that one must sit in the sun or in the cold to cause oneself pain. Chaza”l determine by means of a “hekesh” that just as the prohibition of doing work on Yom Kippur is a negative command, so to the mitzvah of causing suffering is a negative command. Chaza”l learn from here that it means to refrain from eating.
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Rabbi Aharon Dovid Singer
Rosh Kollel, North Miami Beach Community Kollel
Director, South Florida Torah Initiative