Although both Samael and Lilith are major demons in earlier Jewish traditions, they do not appear paired until the second half of the thirteenth century, when they are introduced together. Lilith is a demon created alongside Adam, originally created for the role Eve would fill, who then becomes Samael's bride. With her, Samael created a host of demon children, including a son, the "Sword of Samael" (or of Asmodai).
