Genesis 16
2 Ref Sarai said to Abram," See now, Yahweh has restrained me from bearing. Please go in to my handmaid. It may be that I will obtain children by her." Abram listened to the voice of Sarai.
3 Ref Sarai, Abram's wife, took Hagar the Egyptian, her handmaid, after Abram had lived ten years in the land of Canaan, and gave her to Abram her husband to be his wife.
4 Ref He went in to Hagar, and she conceived. When she saw that she had conceived, her mistress was despised in her eyes.