But Sarai, Abram's wife, had no children. So Sarai took her servant, an Egyptian woman named Hagar,
and gave her to Abram so she could bear his children. "The LORD has kept me from having any children," Sarai said to Abram. "Go and sleep with my servant. Perhaps I can have children through her." And Abram agreed.
So Sarai, Abram's wife, took Hagar the Egyptian servant and gave her to Abram as a wife. (This happened ten years after Abram first arrived in the land of Canaan.)
So Abram slept with Hagar, and she became pregnant. When Hagar knew she was pregnant, she began to treat her mistress Sarai with contempt.
Then Sarai said to Abram, "It's all your fault! Now this servant of mine is pregnant, and she despises me, though I myself gave her the privilege of sleeping with you. The LORD will make you pay for doing this to me!"
References for Genesis 16:5
Abram replied, "Since she is your servant, you may deal with her as you see fit." So Sarai treated her harshly, and Hagar ran away.