Mishnah Shabbat 19

¹Rabbi Eliezer says: if one did not bring an instrument [with which to circumcise] on the eve of Shabbat, he must bring it on Shabbat uncovered; but in [times of] danger he hides it on the testimony of witnesses. Rabbi Eliezer said further: one may cut wood to make charcoal to make an iron instrument. Rabbi Akiva stated a general principle: any [manner of] work which could be performed on the eve of Shabbat does not supersede Shabbat; but that which could not be performed on the eve of Shabbat does supersede Shabbat. ²They may perform all the necessities of circumcision on Shabbat: circumcising, uncovering [the corona], sucking [the wound], and placing a compress and cumin upon [the wound]. If one did not grind [the cumin] on the eve of Shabbat, he may chew [it] with his teeth and apply [it to the wound]. If he did not beat up wine and oil on the eve of Shabbat, he should apply each separately. They may not make a cloak for it in the first place, but he may wrap a rag about it. If this was not prepared from the eve of Shabbat, he may wind it about his finger and bring it, and even from another courtyard. ³They bathe the infant both before and after the circumcision, and sprinkle [warm water] over him by hand but not with a vessel. R. Elazar ben Azaryah says: they may bathe an infant on the third day [of circumcision] which falls on the Shabbat, as it is said, “And it came to pass on the third day, when they were sore” (Genesis 34:25). For one who about whom it is doubtful, and a hermaphrodite, they may not desecrate Shabbat But Rabbi Judah permits [it] in the case of a hermaphrodite. ⁴If a man has two infants, one to circumcise after Shabbat and the other to circumcise on Shabbat, and he forgets and circumcises the one who should be circumcised after Shabbat on the Shabbat, he is liable. [If he has] one to circumcise on the eve of Shabbat and another to circumcise on Shabbat, and he forgets and circumcises the one who should be circumcised on the eve of Shabbat on Shabbat: Rabbi Eliezer holds [him] liable to a sin-offering, but Rabbi Joshua exempts [him]. ⁵An infant is circumcised on the eighth, ninth, tenth, eleventh, and twelfth [days], neither before nor later. How so?In the normal situation, on the eighth. If he is born at twilight, on the ninth; At twilight on the eve of Shabbat, on the tenth. If a festival follows Shabbat, on the eleventh. If the two days of Rosh Hashanah [follow Shabbat], on the twelfth. An infant who is sick is not circumcised until he recovers. ⁶These are the shreds which invalidate circumcision: flesh that covers the greater part of the corona; and he may not eat terumah. And if he is chubby, he must repair it for appearance sake. If one circumcises but does not uncover the circumcision, it is as though he has not circumcised.