After the flood when Noah offers animal sacrifices, God withdraws from earth. Upon smelling the incense of the animals’ flesh, He first acknowledges that human beings’ hearts have an evil inclination from youth onwards (Gen 8:21), promises that He will no longer destroy all life on earth, allows the consumption of animal flesh (ibid. 9:3), and announces within one and the same phrase the prohibition of bloodshed and the murderer’s capital punishment, to be administered and executed by humans themselves: “Whoever sheds a man’s blood, by a man shall his blood be shed; for in the image of God He made man” (Gen 9:6).
The human being’s role as judge is new: Even though Cain, after having killed his brother Abel, fears that someone might kill him on account of his act, God at this point in time still rejects the human’s role as judge and prevents the slaying of Cain. Only after the flood, in this world of Noah, murder is no longer punished by God, but by human beings. The setting up of courts is, accordingly, one of the seven laws that are according to the rabbinic tradition incumbent upon every human being, the “Noahide laws.” From the flood onwards, God, as if disappointed and demoralized by His creatures’ sinfulness, delegates the responsibility to install justice, including capital punishment for murder, to all of humankind.
Intuitively, the two “ends” of Genesis 9:6 – the prohibition of bloodshed and the capital punishment of a murderer at the hands of man – may give rise, at least in a contemporary reader, to a sense of tension, or a paradox: How can God state the absolute inviolability of human life, and at the same time allow human beings to execute capital punishment? The background of this perceived tension is the common formulation of the demand to respect another human being’s life in terms of universal, or natural rights: Each and every human being has a right to physical integrity, the protection of life and well-being, as the notion of life’s immutability is ordinarily articulated in the “modern West.”
The difference between formulating respect for life in terms of universal rights versus as a prohibition of taking an innocent life, may at first seem a difference of form, rather than one of content. Both formulations seem to come down to the same thing: the prohibition of bloodshed. Charles Taylor (Sources of the Self, p. 11) explains that “[t]he difference lies not in what is forbidden but in the place of the subject. Law is what I must obey. It may confer on me certain benefits, here the immunity that my life, too, is to be respected; but fundamentally I am under the law. By contrast, a subjective right is something which the possessor can and ought to act on to put it into effect. To accord you an immunity, formerly given you by natural law, in the form of natural right is to give you a role in establishing and enforcing this immunity. Your concurrence is now necessary, and your degrees of freedom are correspondingly greater. At the extreme end of these, you can even waive a right, thus defeating the immunity.”
In biblical law then, a murderer does not violate an individual’s “natural right” to physical integrity. A murderer commits a transgression that violates God, His “image” in mankind, His law and His entire creation. In line with this, the first commandment – the announcement God makes concerning Himself, “I am the Lord your God who has taken you out of Egypt out of the House of Bondage” – and the sixth commandment – “Do not murder” – were read as parallels: “How were the Ten Commandments given? Five on one tablet and five on another. It is written: I am the Lord your God (Ex 20:1; Deut 5:6) [on one tablet] and parallel to it [on the second tablet] it is written, Do not murder (Ex 20:12, Deut 5:16). Scripture teaches that regarding anyone who spills blood, it is as if he diminishes the image” (Mekhilta de-Rabbi Ishmael, Ba-hodesh, parasha 8). The first commandment is a mirror of the sixth commandment.
When a murderer is punished with humanly imposed death, he is thus not simply sanctioned for violating a divine command, such as any other transgressor: A murderer’s act is of no less than cosmic magnitude and dimension; it leaves a real mark on the world and affects the world as a whole, not just an individual’s “right” to physical protection and wellbeing. Accordingly, a murderer’s guilt is, as mSanhedrin 4:5 expresses, “as if he had destroyed a complete world.”
Murder needs to be addressed by the human community beyond the mere punishment of the murderer: When a murdered body is found and the murderer cannot be identified, a broken-necked heifer atones for the spilling of blood (Deut 21:4-9); and an unwitting murderer has to flee to the “city of refuge” until the death of the officiating High Priest (Num 35:25 and 35:32). Even though in the first case, the murderer cannot be brought to justice and in the second case is deemed undeserving, the land, that was forced to absorb the spilt blood, requires atonement and the exile of the murderer. Murder is, as Devora Steinmetz describes, “[u]nique among crimes in that the act has an essential reality distinct from the legal responsibility of the perpetrator and the possibility of bringing the murderer to justice.”
As an act that effects a human’s relation with the world as a whole, with the land, with God and with other human beings, murder requires of necessity a “repair” at the hands of the world: “Whoever sheds a human’s blood, by a human shall his blood be shed; for in the image of God He made humans” (Gen 9:6) is a chiastic structure, repeating each word of the first clause in reverse order in the second. The second clause virtually mirrors the first, and thereby emphasizes, first, the exact correspondence of offense (murder of man) and punishment (death at the hands of man), and second, the recovery of the creation’s cosmic, metaphysical balance, as if a circle is being closed: When the murderer of man is punished with death by man, what has become out of balance is reinstated, the world’s injury is “fixed,” the land is being atoned for, and cosmic order is reinstalled.
 Cf. Greenberg, “Some Postulates of Biblical Criminal Law,” in Menahem Haran (ed.), Yehezkel Kaufmann Jubilee Volume. Studies in Bible and Jewish Religion dedicated to Yehezkel Kaufmann on the Occasion of his 70th Birthday, Jerusalem: Herbrew University 1960, 5-28 (pp. 15-16): “This view of the uniqueness and supremacy of human life has yet another consequence. It places life beyond the reach of other values. The idea that life may be measured in terms of money or other property, and a fortiori the idea that persons may be evaluated as equivalences of other persons, is excluded. Compensation of any kind is ruled out. The guilt of the murderer is infinite because the murdered life is invaluable. […] The effect of this view is, to be sure, paradoxical: because human life is invaluable, to take it entails the death penalty.”
 “For this reason alone was man created, to teach you, that whosoever destroys a single soul, Scripture imputes guilt to him as if he had destroyed a complete world; and whosoever preserves a single soul, Scripture ascribes merit to him as if he had preserved a complete world” (mSanhedrin 4:5, according to ms Kaufmann A 50, Budapest Akademia, and ms Parma, Biblioteca Palatina, 3173 (דה רוסי 13). According to the Vilna-edition and the ms Jerusalem Yad Harav Herzog of the Bavli, the text reads, “whosoever destroys a single soul of Israel, Scripture imputes guilt to him as if he had destroyed a complete world; and whosoever preserves a single soul of Israel.” Yet, the gemara on this mishnah in bSanhedrin 38a implies that the amoraim are commenting on a version of the mishnah, which does not contain the addition “of Israel.”
 Cf. also Sifre Numbers 161, tKeritot 4:3, bKetubbot 37b, mSota 9:7 and Maimonides, Hilkhot Rotzeah 10:8.
 Steinmetz, “Crimes and Punishments, Part II: Noachide Law, Brother-Sister Intercourse, and the Case of Murder,” Journal of Jewish Studies 55,2 (2004) 278-305.