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Epikoros (or '''Apikoros ''' or Apikores or Epicurus; Hebrew: אפיקורוס, lit. "Heretic", pl. Epicorsim ) is a Jewish term cited in the Mishnah, referring to one who does not have a share in the world to come:
The Rabbinic literature uses merely the term Epikoros, without a specific reference to the Greek philosopher Epicurus, yet it is apparent that the term is derived from the Greek philosopher's name, a philosopher whose views contradicted Jewish scripture, the strictly monotheistic conception of God in Judaism and the Jewish belief in the world to come.
The Talmudic interpretation is that the Aramaic word is derived from the root-word פק"ר (PKR; lit. licentious), hence disrespect, and accordingly:
Maimonides combined the two commentaries, and according to him, scorning a Talmid Chacham is actually a singular case of disrespecting the entire Torah or its Rabbinic scholar-sages. In his work Mishneh Torah (Yad, Teshuvah 3:8), Maimonides rules that an Epikoros is a person who denies that God communicates with humans through prophecy, or one who denies the prophecy of Moses, or one who denies God's knowledge of the affairs of humans 1 (i.e., one who maintains there is no Divine Providence). Maimonides probably encountered the name of Epicurus, the Greek philosopher, some time after composing his Commentary on the Mishnah and before composing the Guide of the Perplexed. In the first source he erroneously states that the rabbinic term, epikoros, is an Aramaic word, but in the Guide he has already become of aware of the atheistic doctrine of the philosopher by that name. He cites the source of his information as Alexander of Aphrodisias' treatise On Providence.
Following the Christian censorship of the Talmud, starting with the aftermath of the Disputation of Barcelona and during the Roman Inquisition and the Spanish Inquisition, the term spread within the Jewish classical texts, since the censorship's authorities would not view with favour, expressions like Minim ("sectary"), which they viewed referring to the Christian faith, and replaced them with the term Epikoros or Epicurus, hence an heretic, since the church would also fight the heretics.