פיקוח נפש בשבת

They said about Hillel the Elder that each and every day he would work and earn a half-dinar, half of which he would give to the guard of the study hall and half of which he spent for his sustenance and the sustenance of the members of his family. One time he did not find employment to earn a wage, and the guard of the study hall did not allow him to enter. He ascended to the roof, suspended himself, and sat at the edge of the skylight in order to hear the words of the Torah of the living God from the mouths of Shemaya and Avtalyon, the spiritual leaders of that generation. The Sages continued and said: That day was Shabbat eve and it was the winter season of Tevet, and snow fell upon him from the sky. When it was dawn, Shemaya said to Avtalyon: Avtalyon, my brother, every day at this hour the study hall is already bright from the sunlight streaming through the skylight, and today it is dark; is it perhaps a cloudy day? They focused their eyes and saw the image of a man in the skylight. They ascended and found him covered with snow three cubits high. They extricated him from the snow, and they washed him and smeared oil on him, and they sat him opposite the bonfire to warm him. They said: This man is worthy for us to desecrate Shabbat for him.

(2) For someone who has a dangerous illness, it is a commandment to break Shabbat for him. One who hurries to do this is praised. One who asks about this is a murderer.

(10) Every illness that the doctors say is dangerous, even though it is external on the flesh, they desecrate Sabbath for it. And if one doctor says [the treatment] is necessary [to save the patient's life] and one doctor says it is not necessary, they desecrate [the Sabbath by treating the patient]. And there is someone who says that it does not require an expert, because everyone is considered a bit of an expert, and a doubt when a life is at stake is resolved leniently. Gloss: Some say this is specifically regarding a Jew [that a nonexpert is relied upon] but ordinary nonJews who are not doctors are not treated like experts...