לא תעמוד על דם רעך

(1) Anyone who kills a human being has violated a ban, as is written: "You shall not murder" (Ex. 20, 12; Deut. 5:16). If someone deliberately commits murder, in the presence of witnesses, he is executed by the sword; for it is written: "This will be avenged" (Ex. 21:20), with which tradition indicates is the execution by the sword. Even if the murderer did his deed by iron or fire, his execution is always carried out with the sword.

(4) And the court is warned not to take a ransom from the murderer, even if they give all of the money in the world, and even if the redeemer of blood wishes to exempt them. For the life of this person who was killed is not the possession of the redeemer of blood but rather the possession of the Holy One Blessed be He as it says, "Do not take a ransom for the life of a murderer." And there is nothing that the Torah is more exacting about than bloodshed as it says, "You shall not pollute the land..." (Numbers 35:33) "...for blood pollutes the land...".

(5) When a murderer kills willfully, he should not be killed by witnesses or observers until he is brought to court and sentenced to death, as implied by Numbers 35:12 "A murderer should not be put to death until he stands before the congregation in judgment." This law applies to all those liable for execution by the court, who transgressed and performed the forbidden act. They should not be executed until their trial is completed by the court.

(6) When does the above apply? When the person has already transgressed and performed the transgression for which he is liable to be executed by the court. When, however, a person is pursuing a colleague with the intention of killing him - even if the pursuer is a minor - every Jewish person is commanded to attempt to save the person being pursued, even if it is necessary to kill the pursuer.

(7) What is implied? If the rodef was warned and continues to pursue his intended victim, even though he did not acknowledge the warning, since he continues his pursuit he should be killed. If it is possible to save the pursued by damaging one of the limbs of the rodef, one should. Thus, if one can strike him with an arrow, a stone or a sword, and cut off his hand, break his leg, blind him or in another way prevent him from achieving his objective, one should do so. If there is no way to be precise in one's aim and save the person being pursued without killing the rodef, one should kill him, even though he has not yet killed his victim. This is implied by Deuteronomy 25:11-12, which states: "If a man is fighting with his brother, and the wife of one... grabs the attacker by his private parts, you must cut off her hand; you may not show pity."

(8) There is no difference whether she grabs "his private parts" or any other organ that imperils his life. Similarly, the rodef may be a man or a woman. The intent of the verse is that whenever a person intends to strike a colleague with a blow that could kill him, the pursued should be saved by "cutting off the hand" of the rodef. If this cannot be done, the victim should be saved by taking the rodef's life, as the verse continues: "you may not show pity."

(9) This, indeed, is one of the negative mitzvot - not to take pity on the life of a rodef. On this basis, our Sages ruled that when complications arise and a pregnant woman cannot give birth, it is permitted to abort the fetus in her womb, whether with a knife or with drugs. For the fetus is considered a rodef of its mother. If the head of the fetus emerges, it should not be touched, because one life should not be sacrificed for another. Although the mother may die, this is the nature of the world.

10)

The laws of a rodef apply whether a person is pursuing a colleague with the intent of killing him, or a maiden that had been consecrated with the intent of raping her, as reflected by Deuteronomy 22:26, which establishes an equation between murder and rape, stating: "Just as when a man arises against his colleague and kills him, so too, is this matter i.e., the rape of a consecrated maiden."

The same principle is reflected by another verse within the passage, which states (Ibid.:27): "The consecrated maiden cried out, but there was no one to save her." Implied is that if there is someone who can save her, he must do so, using all means including taking the life of the pursuer.

13) When a person could prevent a murder or a rape by maiming the rodef's limbs, but did not take the trouble and instead saved the victim by killing the rodef, he is regarded as one who shed blood and is liable for death. Nevertheless, he should not be executed by the court.

(14) Anyone who can save and does not save transgresses 'do not stand by the blood of your neighbour'. So too one who sees his friend drowning in the sea, bandits attacking him or a bad animal attacking him and he is able himself to save him or he could hire others to save him but he does not; one who hears idol worshippers or informers plotting harm for him or laying a trap for him and he doesn't tell his friend and inform him; or if he knows that an idol worshipper or a thug are on their way to his friend and he could appease them on behalf of his friend to change their intention and he doesn't appease him; and so too any similar case; One who does any of these transgresses 'do not stand idly by your neighbour's blood'.

(15) The one who sees a pursuer going after his friend to kill him or after a woman to rape her and is able to save [the pursued] and does not, this one has cancelled a positive commandment: "and cut off her hand" (Deut. 25:12) and has transgressed two negative commandments: "do not turn away your eyes" (Deut. 25:12) and "do not stand idly by your neighbor's blood" (Lev. 19:16).

(16) And even though we do not give lashes on negative commandments because there are no "deeds" in them, nevertheless they are very serious, since every person who kills a soul from Israel is considered as having destroyed the entire world, and every person who sustains/establishes one soul from Israel is considered as having established the entire world.

This is taught in bavli, Sanhedrin 73a: A baraita: From where is it derived that one who sees another drowning in a river, or being dragged away by a wild animal, or being attacked by bandits, is obligated to save him? The verse states: “You shall not stand idly by the blood of another” (Leviticus 19:16). The Gemara asks about this derivation: But is this really derived from here? It is derived from the verse: “And you shall restore it [vahashevato] to him [lo]” (Deuteronomy 22:2),

If this were derived only from there, I would say that this matter applies only to saving the person in danger by himself, But to trouble himself and hire workers for this purpose, one might say that he is not obligated, Therefore, the verse “Do not stand by the blood of another” teaches us that he must even hire workers...

And the Yerushalmi concludes That aperson is even obligated to take on some risk of danger for this, and I think this is because that person is in certain danger while you only risk the danger.

(8) 8. One who sees a boat with Jews that is endangered at sea or in a flowing river, or an individual being chased by idolaters, it is a commandment to desecrate Shabbat to save them.

If however there is danger for the person who is rescuing the obligation does not apply, for your obligation to your own life takes precedence over the life of another. And even putting yourself in a risk of danger takes precedence over the certain danger of another. But this needs to be weighed carefully to assess the risk of danger, and not to be scrupulous about this, for it is said that one who is scrupulous about this will find themselves in the same situation.