In Judaism, human life is essential and so pikuach nefesh, the obligation to save a life in jeopardy, is considered a major value to uphold. This obligation applies to both an immediate threat and a less grave danger that has the potential of becoming serious. Pikuach nefesh is derived from the biblical verse, “Neither shall you stand by the blood of your neighbor” (Lev. 19:16). According to pikuach nefesh a person must do everything in their power to save the life of another, even donate bodily organs. Ovaday Yosef, the former Sephardic Chief Rabbi of Israel, ruled that one may donate an organ to a person in critical need, so long as it does not put the donor’s life at risk.
It is also permissible to travel on Shabbat to save a person’s life. Maimonides declared that a Jew should take the individual, even if a gentile is present, in order to encourage “compassion, loving-kindness and peace in the world” (Mishneh Torah, 2:3). The laws of the Sabbath may be suspended to provide any necessary medical care to a critically ill individual or to an individual in the likelihood of danger to life. However, if a person has only a lesser infirmity or physical ailment, any violation of Shabbat should be minimal or, if viable, performed by a gentile. The laws of Shabbat may also be deferred for a woman who has just given birth within the last three days, to provide more comfort. A patient is allowed to eat non-Kosher food if it is essential for recovery and, on Yom Kippur, a sick person is forbidden to fast if it will impair their recovery and health.
The Talmud contains several instances where the laws of the Sabbath are to be broken to save the life of another; these occasions include the rescuing a child from the sea, breaking apart a wall that has collapsed on a child, breaking down a door about to close on an infant, and extinguishing a fire (Yoma 84b).
In the case that one must make the choice of saving their own life or that of a companion, Rabbi Akiva states that it is permissible to save your life and not the other. This verdict was rationalized by the biblical verse, “Let him live by your side as your kinsman.” Rabbi Akiva determined that the verse implies that “your life takes precedence over his life.” One can only become a martyr if the option is between death and performing acts of idolatry, illegitimate sexual intercourse, or murder (Sanhedrin 74a-b).