Seder 15: Genesis 17---Sign of the Eternal Covenant

God revealed the details of his promise to Abram and Sarai in stages.  When Ishmael was 13 years old, God came to Abram again.  He repeated his promise that Abram would have many descendants (Gen 17:2).  He also expanded the promise.  Not only would Abram be the father of a great nation (Gen 12:2).  He would be Abraham, the father of many nations (Gen 17:4-5). 

Furthermore Sarai, who remained childless at age 90, would have a son within a year.  She would be Sarah, a mother of many nations. 

When Abraham heard this amazing news he laughed, wondering how such a thing could be possible, and God instructed him to name the promised son Isaac ("he laughs"). 

God emphasized that his covenant with Abraham and his descendants had no expiration date, and he introduced circumcision of males as a sign of the covenant.  This sign would dedicate each new generation of the family to God's service and be a continuing reminder of the miraculous birth that made the family possible.  Circumcision was performed in some other cultures---e.g., Egypt (Jer 9:25-26)---as a coming of age ritual, but in no other culture did the practice have this kind of religious purpose.

Abraham promptly carried out God's directive to circumcise himself and the males in his household (Gen 17:23-27), another example of his faithful obedience to God. 

Approximately two thousand years later, God granted his Spirit to people from outside Abraham's family, adding them to the people of God without a requirement of circumcision.  Paul asserted that those baptized into Christ had received a kind of spiritual circumcision (Col 2:11-15) and became spiritual children of Abraham (Gal 3:27-29).  He observed that in Gen 17, God had introduced circumcision as the sign of an already established covenant relationship with Abraham.  The essence of that relationship was Abraham's faithful allegiance to God, and that same kind of faith characterizes spiritual children of Abraham (Rom 4). 

In his Seder 15 sermon, Rob Wilson reflected on these matters, bringing in additional scriptures.