The Oral Torah contains many details that were not included in the Written Torah. For example, the Fourth Commandment (Ex. 20:10) forbids work on the Sabbath; the Oral Torah (Mishnah Shabbos 7:2) lists 39 categories of forbidden work. The phrase "an eye for an eye" in the Written Torah (e.g., Ex. 21:24) is interpreted in the Oral Torah as referring to the payment of damages -- "the value of an eye for an eye". The details of what must be paid for when one person injures another are given in Mishnah Bava Kama 8:1; they include (if applicable) the value of the damage (how much less is a slave worth if he has lost an eye?); pain and suffering; medical expenses; lost time; and embarrassment. The Oral Torah's amplification of the written verse is as old as the written verse itself; the phrase "an eye for an eye" was never interpreted literally by the Jews.
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