God promised Abraham and his wife, Sarah, that they would have a son, even though they were old.  God's promise was not fulfilled quickly, and Sarah became impatient.  She gave her servant Hagar to Abraham so that they could have a child through her.  However, when Hagar conceived, Sarah became jealous of Hagar and mistreated her.  Hagar fled to a spring in the desert on the road to Shur.  An angel at Shur appeared to Hagar and told her to go back to Sarah, and promised Hagar that she would have a son.