Why does Tosafos (תוספות) permit carrying a knife to a child for brit milah on Shabbos (שבת) when the child could be brought to the knife instead? The key distinction is between choosing methods for necessary actions versus performing optional actions that involve chilul Shabbos. Since zrizus requires the knife to come to the child, this becomes the Torah (תורה)'s preferred method, making the chilul Shabbos permissible.
This shiur provides a deep analysis of Tosafos (תוספות)' questions and answers regarding brit milah on Shabbos (שבת), specifically the debate over bringing a knife to the child versus bringing the child to the knife. Rabbi Zweig identifies a crucial distinction between two cases presented by Tosafos on different sides of the daf. On amud aleph, Tosafos questions why one should be mechallel Shabbos by bringing the knife to the child when one could avoid chilul Shabbos entirely by bringing the child to the knife. On amud bet, Tosafos asks why one shouldn't take a longer route with the knife to avoid chilul Shabbos. The key insight is that these represent fundamentally different types of questions. On amud bet, bringing the knife is a necessary action - the question is merely which method to use, invoking the principle of Reish Lakish who holds that when possible, one should perform mitzvos without aveiros. However, on amud aleph, the entire action of bringing the knife is unnecessary since the child could be brought instead. This represents a different category entirely - not a choice between methods of performing a required action, but whether to perform an unnecessary action that involves chilul Shabbos. Tosafos answers that the Torah (תורה) specifically wants the knife to be brought because of the principle of zrizus (alacrity) - the Torah prefers that brit milah be performed quickly. This is derived from other sources that show zrizus is an integral part of the mitzvah (מצוה) of brit milah itself. Once the Torah wants the knife brought (rather than the child), this becomes the required action, and one may be mechallel Shabbos to accomplish it. The distinction explains why Tosafos doesn't invoke Reish Lakish's principle on amud aleph - because Reish Lakish only applies when choosing between methods of performing a necessary action, not when the action itself is optional. This analysis has broader implications for understanding when chilul Shabbos is permitted for mitzvos and the difference between necessary and optional actions in halacha (הלכה).
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Shabbos 130a
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Why does the Gemara say one Shabbos protects from Amalek while two Shabboses bring redemption? The shiur applies a principle from Kiddushin about repetition changing psychology: the first time doing anything is experimental, but the second demonstrates genuine desire. True Shabbos connection with Hashem requires moving beyond spiritual curiosity to authentic internalization.
