The Midrash relates that Hagar was Sarai’s own “property” (not Abram’s) and she had raised her to be righteous. Thus, she would be a suitable consort for Abram. Sarai freed her from slavery and offered her to her husband. Abram agreed at her urging to father a child with Hagar. Once she was pregnant with her master’s child, Hagar’s demeanour towards Sarai changed and the text says Sarai was lowered in Hagar’s esteem. Sarai complained to Abram, who was in an untenable position, torn between loyalty to Sarai and care for the mother of his baby. Abram told Sarai to act as she saw fit. The Ramban says that Sarai sinned by maltreating Hagar while Abram sinned by permitting it.