Genesis 17
by Pastor David Groendyk

In Genesis 17, we have the covenant with Abraham, part III. God has revealed different aspects of his covenant to Abraham in chapter 12, chapter 15, and now chapter 17. But before getting into the specifics of this chapter, pay attention again to the timeline of events. In chapter 12, Abraham was 75 years old when he was promised offspring; in chapter 16, he was 85 years old when he had Ishmael; now, in chapter 17, he’s 99 years old. It might sound crazy for Abraham and Sarah to be doubting God so much (and laughing at him) since he’d appeared to them, but keep in mind that it’s been 24 years since God first made his promise to Abraham, and still he has no child with Sarah. We can all learn from Abraham and Sarah’s (bad) example: God delaying to fulfill a promise does not mean he’s forgotten it.

On to the covenant itself. In chapter 12, God revealed his fourfold promise to Abraham. In chapter 15, he established a covenant with Abraham. Now, in chapter 17, he gives Abraham the sign of the covenant: circumcision. What is a sign? At the risk of over-simplifying it, a covenant sign is something physical that reminds you of God’s covenant. Every covenant that God makes in Scripture comes along with something physical and tangible that God’s people could see or taste or touch. The first covenant with Adam and Eve (before the fall) had the Tree of Life; the covenant with Noah had the rainbow; the covenant with Moses had the Sabbath Day; the new covenant with Christians has baptism and the Lord’s Supper. Why did God give his people covenant signs along with the covenants? Or, to put it another way, what purpose do they serve? One purpose is that they are ‘signs’. In other words, they are a picture of and point us to the covenant. Every single time an Israelite were to circumcise their son and perform the ritual, it would remind everyone involved that God had made promises to make a great nation of Abraham’s offspring, bless them, be with them, give them land, and bless the world through them. It would bring to mind the words that God told Abraham he would do (vv. 4–8) and the subsequent trust and obedience that the people owed God (vv. 1–3). Another reason is that they are ‘seals’. In other words, they reaffirm and confirm the truth of the promises. Remember that Abraham wavers in his faith and commitment time and time again. Indeed, it is the natural tendency of all God’s people to doubt. The covenant sign strengthens the assurance that what God had spoken many, many years ago was true and would not be broken.

The upshot of this is that the covenant signs are gracious aids for God’s people to help their faith. If you put yourself in Abraham’s shoes, you can feel just how difficult it was for him to believe, especially when God only spoke to him on average once every twelve years! Abraham—and all of God’s people—are not left to struggle to remember bare words that were spoken long ago. Rather, because we are human, God gives us physical and tangible reminders of his promises and his covenant. They are his kindness to us. What’s more, God commands us to perform the signs. He commands us to do the very things that help our faith and renew our commitment to him. A full-orbed understanding of the covenant signs should help all of us as the church to appreciate, love, guard closely, and celebrate baptism and the Lord’s Supper as richly theological and deeply significant pictures of the gospel.