"Bilhah (בִּלְהָה "unworried", Standard Hebrew Bilha, Tiberian Hebrew Bilhâ) is a woman mentioned in the Book of Genesis. Genesis 29:29 describes her as Laban's handmaid, who was given to Rachel to be her handmaid on Rachel's marriage to Jacob. When Rachel failed to have children, Rachel gave Bilhah to Jacob as a concubine to bear him children. Bilhah gave birth to two sons, whom Rachel claimed as her own and named Dan and Naphtali. Genesis 35:22 expressly calls Bilhah Jacob's concubine, a pilegesh.
The apocryphal Testament of Naftali says that Bilhah and Zilpah's father was named Rotheus. He was taken into captivity but redeemed by Laban, Rachel and Leah's father, who gave Rotheus a wife named Euna, who was their mother. On the other hand, the early rabbinical commentary Pirke De-Rabbi Eliezer and other Rabbinic sources (Midrash Rabbah, and elsewhere) state that Bilhah and Zilpah were also Laban's daughters, through his concubines, making them half-sisters to Rachel and Leah." - (en.wikipedia.org 12.08.2021)
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