9 One day Sarah saw the son that Hagar the Egyptian had borne to Abraham, poking fun at her son Isaac. 10 She told Abraham, "Get rid of this slave woman and her son. No child of this slave is going to share inheritance with my son Isaac!" 11 The matter gave great pain to Abraham - after all, Ishmael was his son. 12 But God spoke to Abraham, "Don't feel badly about the boy and your maid. Do whatever Sarah tells you. Your descendants will come through Isaac. 13 Regarding your maid's son, be assured that I'll also develop a great nation from him - he's your son too."
14 Abraham got up early the next morning, got some food together and a canteen of water for Hagar, put them on her back and sent her away with the child. She wandered off into the desert of Beersheba. 15 When the water was gone, she left the child under a shrub 16 and went off, fifty yards or so. She said, "I can't watch my son die." As she sat, she broke into sobs. 17 Meanwhile, God heard the boy crying. The angel of God called from Heaven to Hagar, "What's wrong, Hagar? Don't be afraid. God has heard the boy and knows the fix he's in. 18 Up now; go get the boy. Hold him tight. I'm going to make of him a great nation." 19 Just then God opened her eyes. She looked. She saw a well of water. She went to it and filled her canteen and gave the boy a long, cool drink. 20 God was on the boy's side as he grew up. He lived out in the desert and became a skilled archer. 21 He lived in the Paran wilderness. And his mother got him a wife 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.