613 commandments

The tradition that 613 commandments (Hebrew: תרי"ג מצוות‎, taryag mitzvot, "613 mitzvot") is the number of mitzvot in the Torah, began in the 3rd century CE, when Rabbi Simlai mentioned it in a sermon that is recorded in Talmud Makkot 23b.

These principles of Biblical law are sometimes called connections or commandments (mitzvot) and referred to collectively as the "Law of Moses" (Torat Moshe, תורת משה‎), "Mosaic Law", "Sinaitic Law", or simply "the Law". The word mitzvot is plural; singular is mitzvah.

Although there have been many attempts to codify and enumerate the commandments contained in the Torah, the most traditional enumeration is Maimonides'. The 613 commandments include "positive commandments", to perform an act (mitzvot aseh), and "negative commandments", to abstain from certain acts (mitzvot lo taaseh). The negative commandments number 365, which coincides with the number of days in the solar year, and the positive commandments number 248, a number ascribed to the number of bones and main organs in the human body (Babylonian Talmud, Makkot 23b–24a). Though the number 613 is mentioned in the Talmud, its real significance increased in later medieval rabbinic literature, including many works listing or arranged by the mitzvot. Three types of negative commandments fall under the self-sacrificial principle yehareg ve'al ya'avor, meaning "One should let oneself be killed rather than violate it". These are murder, idolatry, and forbidden sexual relations.

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