Genesis 21:9-19

9 And Sarah saw the son of Hagar the Egyptian, whom she had borne unto Abraham, mocking.
10 Therefore she said unto Abraham, "Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, even with Isaac."
11 And the thing was very grievous in Abraham's sight because of his son.
12 And God said unto Abraham, "Let it not be grievous in thy sight because of the lad, and because of thy bondwoman. In all that Sarah hath said unto thee, hearken unto her voice; for in Isaac shall thy seed be called.
13 And also of the son of the bondwoman will I make a nation, because he is thy seed."
14 And Abraham rose up early in the morning, and took bread and a bottle of water; and he gave it unto Hagar, putting it on her shoulder, and the child, and sent her away. And she departed and wandered in the wilderness of Beersheba.
15 And the water in the bottle was spent, and she cast the child under one of the shrubs.
16 And she went and sat down apart from him a good way off, as it were, a bowshot; for she said, "Let me not see the death of the child." And she sat opposite him, and lifted up her voice and wept.
17 And God heard the voice of the lad; and the angel of God called to Hagar out of heaven and said unto her, "What aileth thee, Hagar? Fear not, for God hath heard the voice of the lad where he is.
18 Arise; lift up the lad and hold him in thine hand, for I will make him a great nation."
19 And God opened her eyes and she saw a well of water; and she went and filled the bottle with water, and gave the lad drink.