The text claims that God created Lilith and Adam at the same time, from the same earth. Lilith refused to be subservient to Adam (specifically refusing to lie beneath him during intercourse), arguing they were equals. When Adam tried to force her, she uttered the ineffable name of God and flew away. Three angels (Senoy, Sansenoy, and Semangelof) were sent to retrieve her, but she refused to return, cementing her role as a demon who harms infants.
The Zohar: The foundational work of Kabbalah pairs Lilith with Samael (the angel of death or Satan). She is depicted as the embodiment of the "other side" (the Sitra Achra or evil realm), a seductress of men, and a punisher of sins.