The purposes of this paper are (1) to outline the early Jewish traditions concerning Lilith so as to provide the backdrop for (2) the reconstruction of the main elements of her image in the Alphabet of Ben Sira [ABS] which contains the most elaborate variant of the Lilith-myth. The latter in turn will be (3) confronted with the early rabbinic traditions concerning Eve so as (4) to present the role of Lilith in unburdening Eve of her problematic past on the one hand and (5) to acknowledge the role of Eve in elevating Lilith to the position of the "prototypical" Jewish femme fatale. The conclusions are that (1) the image of Lilith in the ABS draws from the traditions arose around Eve in the early rabbinic literature; (2) the main difference lies in the fact that Lilith is portrayed as far more defined and unambiguous; (3) one of the functions of Lilith in the ABS is to promote the positive image of Eve.