From Parsha to Halakha: Shemot Our obligation to save a life
“He saw an Egyptian man beating a Hebrew man of his kin”
Rambam brings several examples for the mitzvah “Lo ta’amod al dam rei’ekha,” “Do not stand idly by the blood of your fellow,” including: “Or when a Gentile tries to kill him and we can change his mind or prevent the injury.” This description differs slightly from the Talmudic language and is reminiscent of one of the few glimpses we have into Moshe’s “origin story.” Moshe comes across an Egyptian beating an Israelite man to death and kills the Egyptian attacker to save the Israelite victim.
The obligation to save another
Chazal understood that one is obligated to save another when able – be it physical, spiritual/psychological, or financial rescue (which is also learned from the Torah obligations of returning lost objects and bearing testimony one knows on another’s behalf). The verse “Do not stand idly by the blood of your fellow” is the source of a mitzvat lo ta’aseh, a prohibition against indifference and inaction, but the sages also cite a source for a positive mitzvah to save another. In the verses that discuss the rape of a betrothed woman (na’ara me’urasa) the Torah states, “If he found her in the field, the betrothed woman screamed and there was no one to save her.” The sages concluded that there’s an obligation to save a woman from sexual assault using any means necessary (at least in cases when there is also an element of erva – prohibited sexual relationships).
And since society has a tendency to blame rape victims, the Torah also presents a metaphor, “just as a man rises up against his fellow and kills him, so is this matter.” Based on these words the sages also derived a Torah obligation to save a person in mortal danger. This law is generally known as “din rodef,” the law of the pursuer, as the mishna teaches: “These are the ones who are saved with their lives: a man who pursues another to kill them, or a man or a betrothed woman (the latter two with the intent of rape). But one who pursues an animal (for sexual relations), desecrates the Shabbat, or serves false gods is not saved with their life.”
The actions listed are all mortal sins, but not all such attempts should be prevented by any means, even if the cost of the sinner’s life. Such extreme action is reserved for crimes that cause injury to another human. According to Rav Shimshon Raphael Hirsch this involves an aspect of “reut” – fellowship – care for the other.
The value of saving a life is so important it overrides many other mitzvot. Not only is a person permitted to transgress prohibitions like eating non-kosher food to save their own life, they’re also permitted to do so to save the life of someone else. Pikuakh nefesh, saving a life, overrides Shabbat, Yom Kippur and many other prohibitions.
There are only three prohibitions that may not be transgressed to save lives – avoda zara (foreign worship), gilui arayot (prohibited sexual relations), and shfikhut damim (spilling blood). And with the latter, one may kill the aggressor in order to save the life of their potential victim.
At any cost?
The prioritization of pikuach nefesh over other mitzvot is evidence of the unfortunate truth that there is often a heavy price to pay to save a life. The sages determined that one must spend money to save a life, and when the person who was rescued has money, they are obligated to repay the one who saved them. Whether a person must risk life or limb to save another, like donating an organ or entering a burning building, is debatable.
On the one hand there is the famous dispute between Rabbi Akiva and Ben Petura about two travelers, only one with a canteen of water, and they don’t know when they will be able to refill. Ben Petura expects them to share the water, but Rabbi Akiva maintains that a person must prioritize their own needs and is not obligated to put themselves at risk for another. The guidelines about prioritizing tzedaka (charity) also assume that one should prioritize themselves and their family, even if it comes at the expense of those more removed. On the other hand, the Yerushalmi concludes that one must put themselves at risk to save another.
If we return to the story in the Torah we can see that Moshe did take some risks to defend the Hebrew man from the Egyptian, but it also seems that he evaluated and minimized those risks: “He turned this way and that way and saw that there was no person, and he struck the Egyptian and buried him in the sand.”
When God sent Moshe back to Egypt to save Israel, God told him, “Go return to Egypt, for all the people who seek your death have died.” This leads some commentaries to conclude that Moshe would not have put his life in immediate danger, even if he had a chance to save the entire People of Israel. Others argue that such a conclusion is farfetched. Alternatively, some halakhic authorities reason that one is not obligated to put their life at risk to save others, while others claim that such risk is midat chassidut – pious. In general, such decisions should only be made after careful assessment of the risks and rewards.
In times of war
At this time, when we are at war, it’s important to emphasize the magnitude of the mitzvah those who put themselves at risk to save Israel are performing. The Cohen Mashuakh Milkhama, the Priest appointed to accompany the soldiers to battle, excuses some soldiers, “lest he should die in battle.” Everyone is aware that people die in battle, but they go out to fight anyway. The considerations of war are different from those of saving individuals. Soldiers have to turn their backs on their families to face mortal danger in defense of the People of Israel and State of Israel. There is no end to the gratitude we owe them – those who fell in battle and gave their lives as well as those who put their lives on hold to risk life and limb to save us all.
 Sefer HaMitzvot Lo Ta’aseh 297.
 Moshe was forced to flee Egypt when his actions became public. This may explain why the Torah juxtaposes the prohibition of “lo ta’amod” to the prohibition against gossip. (Vayikra 19:7) The only way Moshe could safely save his fellow was because Moshe (mistakenly) thought he wouldn’t gossip. By talking about Moshe’s actions this person transgressed the prohibition of “lo ta’amod.” (As Ibn Ezra and Bechor Schor explain.)
 Devarim 22:27.
 ibid 26
 Sanhedrin 8:7.
 The issue of spilling blood comes up in scenarios when someone needs to kill one person to save another. This question has been discussed at length, beginning on the Tosefta (Terumot 7:23) and gemara (TY Terumot 8:4) and the halakhic rulings in Shulkhan Arukh (Choshen Mishpat 427).
These sources conclude that one may exchange lives – hand one person over for execution in order to save another, unless the executioners demand a particular person. Even then the sages debate if the identity of this person is immaterial (according to Rabbi Yochanan) or if it’s only permissible to hand them over if they have incurred the punishment (Reish Lakish’s opinion). Rema brings both opinions in YD 157:1.
More complex questions follow – Chazon Ish ruled that one may redirect an arrow on the path to injure several people so it only hits one person. (Chazon Ish, Sanhedrin 25) Others dispute his ruling. (Tzitz Eliezer 15:70)
 For more about the obligation to rescue money see TB Sanhedrin 73a; Shulkhan Arukh Choshen Mishpat 426:1. The obligation to repay the savior appears in Rosh Sanhedrin ibid and Beit Yosef Choshen Mishpat 426. Shulkhan Arukh, though, does not mention this law, but Be’er Heitev cites Rema in Yoreh Deah 254:12 who points out that one must lay out money to rescue captives, but the captive is obligated to repay their rescuer.
 TB Bava Metzia 62a.
 For example TB Bava Metzia 71a; Shulkhan Arukh YD 251:3-4.
 Kesef Mishna on Rambam Hilkhot Rotzeakh v’Shmirat haNefesh 1:14, citing Hagahot Maimoniyot citing Talmud Yerushalmi. Shulkhan Arukh does not bring this halakha.
 Shemot 2:12. Both checking that there are no witnesses and hiding the body in the sand demonstrate Moshe’s desire to keep his actions secret. While Rashi and others cite a midrash that Moshe looked to make sure no good people would have been born from the Egyptian, the plain meaning of the text is that he looked to make sure there were no witnesses. (See Malbim and Rabbi Shimshon Raphael Hirsch). Another possible interpretation is that Moshe checked that there was no one stronger than him around who could step up. (See Ha’Ktav v’haKabala)
 Shemot 4:19.
 See Mishna Makot 2:6; Rambam Hilkhot Rotzeakh 7:8; Ohr Sameach ibid.
 See the discussion in Responsa Ridbaz Vol. III 627; Igrot Moshe YD 174; Pitchei Teshuva Choshen Mishpat 426:2.
 Mishpat Cohen 142-144, and see Rav Yaakov Ariel on https://www.toraland.org.il/24309.