Definition and methods
The term lex talionis does not always and only refer to literal eye-for-an-eye codes of justice (see rather mirror punishment) but applies to the broader class of legal systems that specify formulaic penalties for specific crimes, which are thought to be fitting in their severity. Some propose that this was at least in part intended to prevent excessive punishment at the hands of either an avenging private party or the state. The most common expression of lex talionis is "an eye for an eye", but other interpretations have been given as well. Legal codes following the principle of lex talionis have one thing in common: prescribed 'fitting' counter punishment for an offence. In the famous legal code written by Hammurabi, the principle of exact reciprocity is very clearly used. For example, if a person caused the death of another person, the killer would be put to death (Hammurabi's code, §230).
Under the right conditions, such as the ability for all actors to participate in an iterative fashion, the "eye for an eye" punishment system has a mathematical basis in the tit for tat game theory strategy.
The simplest example is the "eye for an eye" principle. In that case, the rule was that punishment must be exactly equal to the crime. Conversely, the twelve tables of Rome merely prescribed particular penalties for particular crimes. The Anglo-Saxon legal code substituted payment of wergild for direct retribution: a particular person's life had a fixed value, derived from his social position; any homicide was compensated by paying the appropriate wergild, regardless of intent. Under the British Common Law, successful plaintiffs were entitled to repayment equal to their loss (in monetary terms). In the modern tort law system, this has been extended to translate non-economic losses into money as well. The meaning of the principle Eye for an Eye is that a person who has been injured by another person returns the offending action to the originator in compensation, or that an authority does so on behalf of the injured person. The exact Latin (lex talionis) to English translation of this phrase is actually "The law of retaliation." The root principle of this law is to provide equitable retribution.
Various ideas regarding the origins of lex talionis exist, but a common one is that it developed as early civilizations grew and a less well-established system for retribution of wrongs, feuds and vendettas, threatened the social fabric. Despite having been replaced with newer modes of legal theory, lex talionis systems served a critical purpose in the development of social systems - the establishment of a body whose purpose was to enact the retaliation and ensure that this was the only punishment. This body was the state in one of its earliest forms.
The principle is found in Babylonian Law (see Code of Hammurabi) (1780 BCE). It is surmised that in societies not bound by the rule of law, if a person was hurt, then the injured person (or their relative) would take vengeful retribution on the person who caused the injury. The retribution might be much worse than the crime, perhaps even death. Babylonian law put a limit on such actions, restricting the retribution to be no worse than the crime, as long as victim and offender occupied the same status in society, while punishments were less proportional with disputes between social strata: like blasphemy or laesa maiestatis (against a god, viz., monarch, even today in certain societies), crimes against one's social better were systematically punished as worse.
Roman law moved toward monetary compensation as a substitute for vengeance. In cases of assault, fixed penalties were set for various injuries, although talio was still permitted if one person broke another's limb.
In the Hammurabi Code and Hebrew Law, the "eye for eye" was to restrict compensation to the value of the loss; in the Hammurabic code as being literal, and in the Hebrew Law applying monetarily. Thus, it might be better read 'only one eye for one eye'. The biblical phrase, "an eye for an eye", (עין תחת עין, ayin tachat ayin, literally 'an eye under an eye'), is a quotation from several passages of the Jewish Bible.
Isaac Kalimi explains that the "lex talionis was humanized by the Rabbis who interpreted "an eye for an eye" to mean reasonable pecuniary compensation. As in the case of the Babylonian 'lex talionis', ethical Judaism and humane Jewish jurisprudence replaces the peshat (literal meaning) of the written Torah. Pasachoff and Littman point to the reinterpretation of the lex talionis as an example of the ability of Pharisaic Judaism to "adapt to changing social and intellectual ideas."
The Talmud (in Bava Kamma, 83b-84a), interprets the verses referring to "an eye for an eye" and similar expressions as mandating monetary compensation in tort cases and argues against the interpretations by Sadducees that the Bible verses refer to physical retaliation in kind, using the argument that such an interpretation would be inapplicable to blind or eyeless offenders. Since the Torah requires that penalties be universally applicable, the phrase cannot be interpreted in this manner.
The Oral Law explains, based upon the biblical verses, that the Bible mandates a sophisticated five-part monetary form of compensation, consisting of payment for "Damages, Pain, Medical Expenses, Incapacitation, and Mental Anguish" - which underlies many modern legal codes. Some rabbinic literature explains, moreover, that the expression, "An eye for an eye, etc." suggests that the perpetrator deserves to lose his own eye, but that biblical law treats him leniently. − Paraphrased from the Union of Orthodox Congregations
However, the Torah also discusses a form of direct reciprocal justice, where the phrase ayin tachat ayin makes another appearance (Deuteronomy 19:16-21). Here, the Torah discusses false witnesses who conspire to testify against another person. The Torah requires the court to "do to him as he had conspired to do to his brother" (Deuteronomy 19:19). Assuming the fulfillment of certain technical criteria (such as the sentencing of the accused whose punishment was not yet executed), wherever it is possible to punish the conspirators with exactly the same punishment through which they had planned to harm their fellow, the court carries out this direct reciprocal justice (including when the punishment constitutes the death penalty). Otherwise, the offenders receive lashes.
Since there is no form of punishment in the Torah that calls for the maiming of an offender, there is no case where a conspiratorial false witness could possibly be punished by the court injuring to his eye, tooth, hand, or foot. (There is one case where the Torah states "…and you shall cut off her hand…" Deuteronomy 25:11-12. The sages of the Talmud understood the literal meaning of this verse as referring to a case where the woman is attacking a man in potentially lethal manner. This verse teaches that, although one must intervene to save the victim, one may not kill a lethal attacker if it is possible to neutralize that attacker through non-lethal injury Sifrei; Maimonides' Yad, Nezikin, Hil. Rotze'ach u'Sh'mirat Nefesh 1:7}. Regardless, there is no verse that even appears to mandate injury to the eye, tooth, or foot.)
Numbers 35:9-30 discusses the only form of remotely reciprocal justice not carried out directly by the court, where, under very limited circumstances, someone found guilty of negligent manslaughter may be killed by a relative of the deceased who takes on the role of "redeemer of blood". In such cases, the court requires the guilty party to flee to a designated city of refuge. While the guilty party is there, the "redeemer of blood" may not kill him. If, however, the guilty party illegally forgoes his exile, the "redeemer of blood", as an accessory of the court, may kill the guilty party. Nevertheless, the provision of the "redeemer of blood" does not serve as true reciprocal justice, because the redeemer only acts to penalize a negligent killer who forgoes his exile. Furthermore, intentional killing does not parallel negligent killing and thus cannot serve directly as a reciprocal punishment for manslaughter, but as a penalty for escaping punishment (Makot 7a-13a). (According to traditional Jewish Law, application of these laws requires the presence and maintenance of the biblically designated cities of refuge, as well as a conviction in an eligible court of 23 judges as delineated by the Torah and Talmud. The latter condition is also applicable for any capital punishment. These circumstances have not existed for approximately 2,000 years.)
Objective of reciprocal justice in Judaism
The Talmud discusses the concept of justice as measure-for-measure retribution (middah k'neged middah) in the context of divinely implemented justice. Regarding reciprocal justice by court, however, the Torah states that punishments serve to remove dangerous elements from society ("…and you shall eliminate the evil from your midst," Deuteronomy 19:19) and to deter potential criminals from violating the law ("And the rest shall hear and be daunted, and they shall no longer commit anything like this evil deed in your midst", Deuteronomy 19:20). Additionally, reciprocal justice in tort cases serves to compensate the victim (see above).
The ideal of vengeance for the sake of assuaging the distress of the victim plays no role in the Torah's conception of court justice, as victims are cautioned against even hating or bearing a grudge against those who have harmed them. The Torah makes no distinction between whether the potential object of hatred or a grudge has been brought to justice, and all people are taught to love their fellow human beings.(Lv 19:17-18).
Social hierarchy and reciprocal justice
In Exodus 21, as in the Code of Hammurabi, the concept of reciprocal justice was only meant to apply to social equals. In Ex 21:23-25 lies the statement of reciprocal justice "life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burn for burn, wound for wound, stripe for stripe" and then following it an example of a different law. If a slave-owner blinds the eye or knocks out the tooth of a slave, the slave is freed but the owner does not pay any other consequence. On the other hand, the slave would probably be put to death for the injury of the eye of the slave-owner.
However, in Leviticus, the reciprocal justice is meant to apply across social boundaries. The "eye for eye" principle is directly followed by the proclamation "You are to have one law for the alien and the citizen." (Lev 24:19-22) This shows a much more meaningful principle for social justice, in that the marginalized in society were given the same rights under the social structure. In this context, the reciprocal justice in an ideal functioning setting, according to Michael Coogan, "to prevent people from taking the law into their own hands and exacting disproportionate vengeance for offenses committed against them."
Lex talionis in Christianity
Christian interpretation of the Biblical passage has been heavily influenced by the Church father St. Augustine. He already discussed in his Contra Faustum, Book XIX, the points of 'fulfilment or destruction' of the Jewish law. George Robinson characterizes the passage of Exodus ("an eye for an eye") as one of the "most controversial in the Bible". According to Robinson, some have pointed to this passage as evidence of the vengeful nature of justice in the Hebrew Bible. Similarly, Abraham Bloch speculates that the "lex talionis has been singled out as a classical example of biblical harshness." Stephen Wylen asserts that the lex talionis is "proof of the unique value of each individual" and that it teaches "equality of all human beings for law." In the Sermon on the Mount), Jesus of Nazareth urges his followers to turn the other cheek rather than to seek legal steps for any compensation that corresponds in kind and degree to the injury:
You have heard that it was said, "An eye for an eye and a tooth for a tooth". But I say to you, do not resist an evildoer. If anyone strikes you on the right cheek, turn to him the other also. (Matthew 5:38-39, NRSV)
This saying of Jesus is frequently interpreted as criticism of the Old Testament teaching, and often taken as implying that "an eye for an eye" encourages excessive vengeance rather than an attempt to limit it.
The Qur'an mentions the "eye for an eye" concept as being ordained for the Children of Israel. The principle of Lex talionis in Islam is Qasas (قصاص) as mentioned in (Qur'an 2:178) "O you who have believed, prescribed for you is legal retribution (Qasas) for those murdered - the free for the free, the slave for the slave, and the female for the female. But whoever overlooks from his brother anything, then there should be a suitable follow-up and payment to him with good conduct. This is an alleviation from your Lord and a mercy. But whoever transgresses after that will have a painful punishment.". Some Muslim nations, still apply the rule, in accordance with the Mosaic Law. In some countries that use Islamic law (sharia), the "eye for an eye" rule is applied quite literally.
"In the Torah We prescribed for them a life for a life, an eye for an eye, a nose for a nose, an ear for an ear, a tooth for a tooth, an equal wound for a wound: if anyone forgoes this out of charity, it will serve as atonement for his bad deeds. Those who do not judge according to what God has revealed are doing grave wrong." (Qurʾān 5:45)
Some alternative penalty systems exist which are not primarily punitive in nature, but instead concern the effect of the punishment on the sanctioned offender, or alternatively on society. These systems provide remediation that might not be strictly reflective of the original offense. For example, many modern penal systems are designed to be correctional or rehabilitative in practice.
The concept of an eye for an eye is generally distinct from its application. In the context of homicide it generally only applies to murder or intentional killings despite the fact that a negligent homicide also results in the loss of a person's life. This application implicitly recognizes that the mens rea element of the crime rather than the actual harm to the victim will ultimately determine the application of an eye for eye justice.