I. Name
The concept of an evil inclination is typically rabbinic. This notion does not occur in the Bible, but the rabbis did derive it from biblical texts (esp. Gen. 2.7; Gen. 6.5; Gen. 8.21). This inclination or drive is sometimes personified as a demonic figure or the Satan.
II. Identity
The widespread Goethean concept ‘zwei Seelen gibt’s in meiner Brust [two souls are in my breast]’ was given expression by the early rabbis in a theory of two yeṣarim (‘inclinations, desires, drives, bents of mind’), namely the yeṣer ha-tov (the desire…