Adultery in Classical Athens

In Classical Athens, there was no exact equivalent of the English term "adultery", but the similar moicheia (Ancient Greek: μοιχεία) was a criminal offence often translated as adultery by scholars. Athenian moicheia was restricted to illicit sex with free women, and so men could legally have extra-marital sex with slaves and prostitutes. Famously, Athenian adultery laws considered seduction of a citizen woman a worse crime than rape.

The act which is usually rendered in English as "adultery" was called moicheia (μοιχεία) in Greek. Moicheia was defined more broadly than the English "adultery", however, referring to any "seduction of a free woman under the protection of a kyrios". Thus, sex with the wife, daughter, or sister of a free man were all considered to be instances of moicheia. In at least one case, detailed in the speech Against Neaera, we know that an alleged moichos was imprisoned based on a father's right to punish moicheia committed against his daughter. In Athenian law, moicheia was always committed by men upon women.

Against this view of moicheia, David Cohen has argued that it was limited to sex with citizens' wives, and that the word moichos was synonymous with the modern English "adulterer", but this view has been largely rejected by other scholars.

Married men were not considered to have committed adultery if they were to have sexual relationships with slaves or prostitutes.

An Athenian law on adultery (graphe moicheias) is known to have existed, though it has not survived. Christopher Carey argues that the law cited at §28 of On the Murder of Eratosthenes is an otherwise unknown law on adultery, which prescribed the actions to be taken in cases of moicheia and specified killing the culprit as an option.

Along with the law on moicheia reconstructed by Carey, three Athenian laws which concerned moicheia have survived, all preserved in the works of fourth-century BC orators. The first of these prohibited a man from living with an adulterous wife, and an adulterous wife from taking part in public religious ceremonies. The second exempted a kyrios who killed a moichos caught in the act.

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