LEV238 … both sibling and wifely rivalry permeated the relationship of two matriarchs, Leah and Rachel. The two women were married to Jacob. Rachel, who was having trouble conceiving, was jealous of her sister Leah, who already had four children (Genesis 30:1). ... Although later Torah law permitted polygamy, it forbade two sisters from marrying the same man, unless one of them had died [this verse].