ACTS BIBLE
Abraham week 11 · Genesis 21:1-7
The LORD visited Sarah as he had said. Twenty-five years after the promise, the house fills with the laughter God named.
And the LORD visited Sarah as he had said, and the LORD did unto Sarah as he had spoken. For Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him (Genesis 21:1-2). Three times in two verses the narrator hammers the same nail: as he had said, as he had spoken, at the set time. Twenty five years separate the promise of Genesis 12 from the cradle of Genesis 21, a quarter century across a famine, a war, two royal harems, a shortcut, and thirteen silent years, and the delivery date lands exactly where chapter 17 set it. The chapter is short because its point is short: God's word arrived on schedule, and nothing else about the story needed to work for that to happen.
Abraham names the boy Isaac, the name God assigned in 17:19, and it means he laughs. The name keeps the whole file: Abraham fell on his face laughing at a hundred-year-old's son (17:17); Sarah laughed at the tent door and denied it (18:12-15). Now Sarah laughs with the whole account reversed: God hath made me to laugh, so that all that hear will laugh with me. Who would have said unto Abraham, that Sarah should have given children suck? (21:6-7). The laughter of unbelief has been transformed into the laughter of joy without being scolded out of her; God simply outlasted it, and then named the baby after it, so that every time the covenant family calls the heir to dinner they preach the sermon again: the LORD gets the last laugh, and it is a kind one.
Circumcised the eighth day per the covenant of chapter 17, weaned with a feast, Isaac is everything Ishmael was not in one respect only: he is the child of promise, born when the flesh was finished. Paul's commentary is blunt about the mechanics: Isaac was born by promise, after the Spirit, of the freewoman (Galatians 4:23, 28-29), and believers are as Isaac was, the children of promise. That is the typology this quiet chapter carries. Every Christian's new birth has Isaac's shape, life produced by God's word against the flesh's arithmetic, born, not of blood, nor of the will of the flesh, nor of the will of man, but of God (John 1:13). Romans 4 had already welded the two together: Abraham's faith in the God who quickeneth the dead over Isaac's conception is the same faith that believes on him that raised up Jesus our Lord from the dead (Romans 4:17-24). Resurrection faith was learned in a nursery.
It is worth sitting in the gladness of this chapter before next week arrives. Scripture is not embarrassed by the feast, the nursing, the mother's laughter; fulfillment is meant to be enjoyed out loud. And the enjoyment is doctrine: every promise kept teaches that the Promiser keeps promises, and this house will need that lesson within a chapter, on a mountain in Moriah. Joy now is the ballast for the test to come.