A Laughable Promise – Genesis 17:15 – 18:15

Abraham Sermon Series - Genesis 17:15 - 18:15This sermon is based on Genesis 17:15 – 18:15. Click here to read the text.

As of Genesis 17:14, Abram is now known as Abraham. He was buoyed by God’s promise that not only would he be the father of a nation, but the father of a multitude of nations. Along with that promise came the covenant sign of circumcision, which served as a sign and seal of God’s covenant promises to Abraham and as a sign of Abraham’s call to faithful living unto God. Beginning in Genesis 17:15, Abraham was shown that God’s plan for Abraham included a miraculous turn of events. God intended to bring life from the newly named Sarah, though she was well past her time for childbearing (Genesis 18:11 indicates that Sarah had been through menopause). Both Abraham (17:17) and Sarah (18:12) responded to this new aspect of God’s covenant with incredulous laughter. Picking up on this, God said that their son would bear the name, Isaac, which means “laughter”.

This promised son was initially made known to Abraham on the same occasion that circumcision was given as the covenant sign. Abraham responded to this news in two chief ways. First, he expressed to God his concern for Ishmael, his thirteen year old son. He asked that Ishmael might “live before” the LORD. Abraham loved Ishmael, and wanted good for him. God answered that Isaac would be the son through whom covenant headship would proceed, but that Ishmael would be fruitful, at least in the here and now. God showed grace and mercy to Ishmael for Abraham’s sake, though His larger purposes were to be fulfilled through Isaac. Second, Abraham obeyed the LORD by receiving the sign of circumcision and by having Ishmael, and every male in his household (servants and foreigners alike, a “mixed multitude” under Abraham’s authority) circumcised. Abraham showed an obedience that was immediate and complete, despite the inconvenience, discomfort, and counter-cultural nature of the command. He obeyed not only as an individual but as a representative head over his people.

The promise of Isaac was reiterated when the LORD appeared to Abraham as three travelers. It was on this second occasion that Sarah overheard the promise. Had Abraham previously shared with her the news that they would conceive a son together, or was this the first time she had heard the news? Either way, she was skeptical of the validity of the prophecy. But the One who was making the promise was none other than the omniscient and omnipotent, El Shaddai the LORD. Nothing is too hard for Him! He spoke the Creation into being. If He could bring light into the darkness and life from nothing in the very beginning He could give Sarah and Abraham laughter in the form of a son, Isaac. Of course God would do an even greater set of miracles in and through Jesus, God the Son Incarnate, who was conceived by the Holy Spirit in the womb of the Virgin Mary and who was resurrected from the dead (life coming from death!). Is anything too hard for our God? The answer is, NO! He who brought light out of darkness, Creation out of nothing, Isaac out of Sarah, and Jesus out of both Mary and the grave, can surely bring us out of sin and death into eternity. He can manifest glimpses of that eternity in us already through changed lives and through amazing circumstances as well. Such is the nature of our gracious God.

Discuss and Pray – Genesis 17:15 – 18:15

  1. Abraham’s obedience (which was response to God’s grace!) when called to be circumcised and to lead all his people to be circumcised was immediate and complete, though it was no doubt inconvenient, uncomfortable, and counter-cultural. How does his example encourage us to obedience that is timely and complete, even if it is inconvenient, uncomfortable, and counter-cultural?
  2. Sarah’s doubts about God’s promised son are understandable, especially given her condition (menopause). Nevertheless, she was rightly rebuked and called to renew her faith in God, for whom nothing is too hard. In what ways does God’s omnipotence encourage you? In the face of what “impossibilities” does His being all-powerful strengthen your resolve? As you consider some of these impossibilities, think not only of personal situations where God’s grace has sustained you but also larger community or cultural situations where God’s people and His Church need(ed) His grace and strength to stand firm by faith in He who is omnipotent.