For one desiring to understand the storyline of Scripture, they dare not blink at this point in the journey. Genesis 15-17 records not only the full expression of the Abrahamic covenant, but also the pattern of faithful, daily spirituality in all richness and honesty. The apostle Paul employed the real-life events of Abraham to illustrate the blessings and allegiance that correspond to faith in Christ.

By the time of Genesis 15, Abraham did not yet have a single blood-line heir—let alone enough posterity to be called a great nation (cf. 12.2). Then the word of the LORD came to him: “Look at the sky and count the stars, if you are able to count them…Your offspring will be that numerous” (v. 5). Abraham responded with courageous faith—and the LORD, “credited it to him as righteousness” (v. 6); this statement would make Abraham the model of faith for all time! God affirmed the patriarch’s faith through the smoking fire pot and flaming torch—reminding the patriarch that he would not only become a great nation, but his descendants would also dwell in a special plot of land (vv. 9-21).

Nevertheless, the first words of Gen 16 reveal that Abram was yet waiting on the fulfillment of God’s promise: “Abram’s wife Sarai had not borne him children” (v. 1). She interpreted God’s delay as a definitive act, saying, “Since the LORD has prevented me from bearing children, go to my slave; perhaps I can have children by her” (v. 2). Abraham failed to respond appropriately in this crisis of faith, and the result was not what Sarah had intended; rather than fulfilled, her life was made bitter by the birth of Ishmael to Hagar (vv. 4-7). One can only imagine the chilly atmosphere of Abram’s home (vv. 9, 15).

Gen 17 records God’s covenant affirmation to Abraham—even years after his unfaithful act with Hagar:

  1. God promised that He would indeed bring many descendants from Abraham and Sarah. To give the patriarch a constant reminder of this promise, God changed his name to Abraham (Hb. “father of nations”). Further, this multitude would have their own territory (vv. 1-8)
  2. The male children born to Abraham were to be marked by circumcision of the foreskin; even male slaves born under his dominion were to receive the sign of the covenant (vv. 9-14). Thus, the anatomical locale of procreation was marked for God’s special purpose. This was to remind the descendants of Abraham that they were indeed a special people, heirs of promise and faith (cf. Gal 4.21-31)
  3. God affirmed that the child of promise would be born to Abraham through Sarah. God even stated the exact time the child would be born! (vv. 15-22)

While several lines of helpful moral instruction could be pursued here (especially the need for marital fidelity!), it may be best to consider how the events in Genesis 15-17 provide the schema of the storyline of Scripture. It may be that the Christian doctrine of salvation is most fully delineated in the New Testament epistles to the Romans and Galatians—and in both Paul employed the faith of Abraham as a model for his readers. To help his audience understand justification by faith in Christ—apart from circumcision and the Mosaic Law—in Paul wed the concept of faith expressed by Abraham in Genesis 15 with the theme of forgiveness in Psalm 32 (Romans 4). His proposition can be summarized by considering the subject and object of our faith. As the subject of faith, we must be made aware of our complete inability to carry out God’s plan—we are as helpless as depleted bodies conceiving a child. In light of our total inability to be saved, we must receive salvation; we cannot earn it (cf. Rom 3.9-24). We must therefore place our hope entirely in the object of our faith—the faithful God who is always true to His promises. Paul wrote:

“What then can we say that Abraham, our forefather according to the flesh, has found? If Abraham was justified by works, then he has something to brag about—but not before God. For what does the Scripture say? ‘Abraham believed God, and it was credited to him for righteousness.’ Now to the one who works, pay is not considered as a gift, but as something owed. But to the one who does not work, but believes on Him who declares righteous the ungodly, his faith is credited for righteousness.

Likewise, David also speaks of the blessing of the man to whom God credits righteousness apart form works: ‘How happy those whose lawless acts are forgiven and whose sins are covered! How happy the man whom the Lord will never charge with sin!’” (Rom 4.1-8; cf. Ps 32.1-2).

The bulk of Paul’s argument to the Galatians was based upon the record of Abraham in Genesis 15-17. To help the Galatians understand that they were justified by faith—as evidenced by the presence of the Holy Spirit, whose presence does not accord circumcision or adherence to the system of the Mosaic Law—Paul set forth the faith (and justification) of Abraham (Gal 3.6-18). Paul was concerned that the Galatians understand their sonship in Christ, apart from the practice of the Law. He argued that those living under it are cursed, and that Christ had redeemed them from its curse. He said the purpose of Christ’s work was “that the blessing of Abraham would come to the Gentiles in Christ Jesus so that we could receive the promise of the Spirit through faith” (v. 14). The chronological flow of the Scripture storyline was fundamental to Paul’s argument; since Abraham received the promise of justification by faith more than 400 years before the Law was given on Mount Sinai, all who had faith like his became heirs apart from the Law. Paul’s conclusion was clear: “So those who have faith are blessed with Abraham, who had faith” (v. 9), and: “If the inheritance is from the law, it is no longer from the promise; but God granted it to Abraham through the promise” (v. 18).


*For a complete list of references, please see