Rabbi Baruch Bodenheim: Gemara Shabbos: Perek Kirah, יום חמישי, Av 20, Daf 40b (08/14/25)

Quickly review the גמרא דף מ: “א”ר יצחק בר אבדימי (middle of the wide lines) until  “היכי עביד הכי” 

Do we conclude lhalacha in accordance with all three?

Learn the רי”ף who has a different Girsa in the third Halacha. 

Learn the ר”ן who explains the difference. 

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Questions:

Why is the bath considered a כלי ראשון?

Learn רש”י “בכלי שני

Learn רש”י “וש”מ הפשרו

What is Rashi adding?

Is it permitted to place water near a fire to warm up when the fire will go out before the water heats up to יד סולדת? 

Learn שולחן ערוך אורח חיים ס’ שי”ח סע’ יד & משנה ברורה ס”ק צ 

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Learn אגרות משה או”ח חלק את ס’ צג

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Learn שמירת שבת כהלכתו פרק א הערה ח

See משנה ברורה ס”ק צא

Why is the case of a timer that will shut off the electricity before the water can get hot different than heating towels? 

Major Question:

Why is it permitted to place uncooked food in a כלי שני? Why should a כלי שני be different than a כלי ראשון if the temperature of the water is still hot enough to cook?

Learn תוס’ “ושמע מינה

What is the exact reason why kli sheini can not cook. Is it because the walls cool down the liquid or is because the walls are not hot?

Would a thermos be considered a kli sheini?

Continue learning the גמרא דף מ. “היכי עביד הכי until “א”ר זירא ” (three lines from the bottom of the Amud) 

Next Gemara deals with the topic of swimming on Shabbos 

Learn the גמרא דף מ: “א”ר זירא (three lines from the bottom of the Amud) until the two dots on top of דף מא