9 But Sarah saw that the son whom Hagar the Egyptian had borne to Abraham was mocking, 10 and she said to Abraham, "Get rid of that slave woman and her son, for that woman's son will never share in the inheritance with my son Isaac." 11 The matter distressed Abraham greatly because it concerned his son. 12 But God said to him, "Do not be so distressed about the boy and your slave woman. Listen to whatever Sarah tells you, because it is through Isaac that your offspring[1] will be reckoned. 13 I will make the son of the slave into a nation also, because he is your offspring."

14 Early the next morning Abraham took some food and a skin of water and gave them to Hagar. He set them on her shoulders and then sent her off with the boy. She went on her way and wandered in the Desert of Beersheba. 15 When the water in the skin was gone, she put the boy under one of the bushes. 16 Then she went off and sat down about a bowshot away, for she thought, "I cannot watch the boy die." And as she sat there, she[2] began to sob. 17 God heard the boy crying, and the angel of God called to Hagar from heaven and said to her, "What is the matter, Hagar? Do not be afraid; God has heard the boy crying as he lies there. 18 Lift the boy up and take him by the hand, for I will make him into a great nation." 19 Then God opened her eyes and she saw a well of water. So she went and filled the skin with water and gave the boy a drink. 20 God was with the boy as he grew up. He lived in the desert and became an archer. 21 While he was living in the Desert of Paran, his mother got a wife for him from Egypt.

Matthew Henry's Commentary on Genesis 21:9-21

Commentary on Genesis 21:9-13

(Read Genesis 21:9-13)

Let us not overlook the manner in which this family matter instructs us not to rest in outward privileges, or in our own doings. And let us seek the blessings of the new covenant by faith in its Divine Surety. Ishmael's conduct was persecution, being done in profane contempt of the covenant and promise, and with malice against Isaac. God takes notice of what children say and do in their play; and will reckon with them, if they say or do amiss, though their parents do not. Mocking is a great sin, and very provoking to God. And the children of promise must expect to be mocked. Abraham was grieved that Ishmael should misbehave, and Sarah demand so severe a punishment. But God showed him that Isaac must be the father of the promised Seed; therefore, send Ishmael away, lest he corrupt the manners, or try to take the rights of Isaac. The covenant seed of Abraham must be a people by themselves, not mingled with those who were out of covenant: Sarah little thought of this; but God turned aright what she said.

Commentary on Genesis 21:14-21

(Read Genesis 21:14-21)

If Hagar and Ishmael had behaved well in Abraham's family, they might have continued there; but they were justly punished. By abusing privileges, we forfeit them. Those who know not when they are well off, will be made to know the worth of mercies by the want of them. They were brought to distress in the wilderness. It is not said that the provisions were spent, or that Abraham sent them away without money. But the water was spent; and having lost their way, in that hot climate Ishmael was soon overcome with fatigue and thirst. God's readiness to help us when we are in trouble, must not slacken, but quicken our endeavours to help ourselves. The promise concerning her son is repeated, as a reason why Hagar should bestir herself to help him. It should engage our care and pains about children and young people, to consider that we know not what great use God has designed them for, and may make of them. The angel directs her to a present supply. Many who have reason to be comforted, go mourning from day to day, because they do not see the reason they have for comfort. There is a well of water near them in the covenant of grace, but they are not aware of it, till the same God that opened their eyes to see their wound, opens them to see their remedy. Paran was a wild place, fit for a wild man; such as Ishmael. Those who are born after the flesh, take up with the wilderness of this world, while the children of the promise aim at the heavenly Canaan, and cannot be at rest till they are there. Yet God was with the lad; his outward welfare was owing to this.