211 And Jehovah visited Sarah as he had said, and Jehovah did unto Sarah as he had spoken. 2 And Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him. 3 And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac. 4 And Abraham circumcised his son Isaac when he was eight days old, as God had commanded him. 5 And Abraham was a hundred years old, when his son Isaac was born unto him. 6 And Sarah said, God hath made me to laugh. Every one that heareth will laugh with me. 7 And she said, Who would have said unto Abraham, that Sarah should give children suck? For I have borne him a son in his old age.
8 And the child grew, and was weaned. And Abraham made a great feast on the day that Isaac was weaned.
9 And Sarah saw the son of Hagar the Egyptian, whom she had borne unto Abraham, mocking. 10 Wherefore she said unto Abraham, Cast out this handmaid and her son. For the son of this handmaid shall not be heir with my son, even with Isaac. 11 And the thing was very grievous in Abraham's sight on account 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 handmaid. In all that Sarah saith unto thee, hearken unto her voice. For in Isaac shall thy seed be called. 13 And also of the son of the handmaid will I make a nation, because he is thy seed.
Matthew Henry's Commentary on Genesis 21:1-13
Commentary on Genesis 21:1-8
(Read Genesis 21:1-8)
Few under the Old Testament were brought into the world with such expectations as Isaac. He was in this a type of Christ, that Seed which the holy God so long promised, and holy men so long expected. He was born according to the promise, at the set time of which God had spoken. God's promised mercies will certainly come at the time which He sets, and that is the best time. Isaac means "laughter," and there was good reason for the name, Psalm 22:9,10; Hosea 11:1,2.
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.