Genesis 20:2-3

2While he was there, Abraham told people that his wife, Sarah, was his sister. Because of this, the king of Gerar took Sarah so that she would become his wife. The king's name was Abimelech.

3But God appeared to Abimelech in a dream. He said to Abimelech, ‘Now you will die! The woman that you have taken to be your wife is already a married woman.’