Shabbat 132B

ועבודה דוחה את השבת ⁠— מילה דוחה אותה. שבת שנדחית מפני העבודה, אינו דין שתהא מילה דוחה אותה?

and the Temple service overrides Shabbat, as Shabbat offerings are sacrificed at their appointed time, and nevertheless circumcision overrides tzara'at, i.e., if there were symptoms of tzara'at on the foreskin of the baby, one circumcises the child even though he thereby violates the prohibition to cut off symptoms of tzara'at; therefore, with regard to Shabbat, which is overridden by the Temple service, is it not logical that circumcision, which is so stringent that it overrides tzara'at, overrides Shabbat as well? This was the tanna’s reasoning at the outset.

ומאי ״או אינו״ דקאמר ⁠— הדר אמר: וממאי דצרעת חמורה? דילמא שבת חמורה, שכן יש בה עונשין ואזהרות הרבה. אי נמי: וממאי משום דחמירא צרעת היא, דילמא משום גברא הוא דלא חזי. ומה אני מקיים ״שמיני ימול״⁠ — חוץ משבת. תלמוד לומר: ״ביום״⁠ — אפילו בשבת.

And what was the reason the tanna said: Or perhaps, and questioned his previous statement? He reconsidered and said: And from where do we know that tzara'at is more stringent than Shabbat? Perhaps Shabbat is more stringent, as it includes the severe punishments of karet and execution by stoning, and numerous warnings pertaining to it throughout the Torah. Alternatively, and from where do we know that the reason the Temple service does not override the prohibition of tzara'at is specifically because tzara'at is more stringent than the Temple service? Perhaps the Temple service does not override the prohibition of tzara'at because a man afflicted with tzara'at is unfit to perform the Temple service and not due to the stringency of the prohibition to remove symptoms of tzara'at from one’s body. And if so, how do I establish the verse: “And on the 8th day the flesh of his foreskin should be circumcised” (Leviticus 12:3)? That it applies to days other than Shabbat. Consequently, the tanna cited additional proof from that which the Torah states: “On the day,” indicating that circumcision is performed even on Shabbat.