After the liberation of Lot, God appeared to Abraham in a vision. God declared that Abraham had divine protection and that his great reward was certain. Abraham now had grave doubts about Sarah bearing him a son. He knew that if he was without a son, God could give him nothing. Concluding that Sarah could not bear a son, he proposed to God an alternate solution. He requested that God accept Eliezer of Damascus, a servant, as his heir.

Abraham’s request was not some curious invention of his own imagination. The Nuzi Tablets document the practice among the Hurrians, who lived in the vicinity of Haran, of childless couples adopting a slave. The slave functioned as their son and became their heir. Abraham was suggesting a known, practiced solution to a threatening problem.¹

God rejected Abraham’s proposal. He declared Abraham’s heir would be from his own body. He also declared that his descendants would be in number as the stars of the heavens.

Upon God’s reassurance, Abraham believed God’s promise. At that point the faith reckoned for righteousness came into existence.

And he (Abraham) believed in Jehovah; and He (Jehovah) reckoned it to him for righteousness (Genesis 15:6).

Only when Abraham trusted God’s promise in the face of his own doubts did God reckon Abraham’s faith for righteousness.

It is important to note that nothing had happened concerning God’s promise of an heir. Sarah was barren in Ur. She was barren in Haran. She was barren in the initial travels in Canaan and in Egypt. She was still barren at this time. Nothing physically indicated she had been given the ability to conceive. In fact, God gave no indication that conception was imminent. God simply affirmed that the son would be born. On nothing more than the promise of God, Abraham believed it would happen. He believed God would keep His promise simply because God declared that He would. He trusted God to keep His promise at a time when Abraham had genuine doubt born of deep concern. That is the faith which God reckoned for righteousness.

Abraham’s concerns were not Abraham’s alone. God’s promises affected Sarah’s life and future as certainly as they affected Abraham’s. Her role in the fulfillment of God’s promises equaled that of Abraham’s. She desired the promised son as fervently as did he. She was as anxious for that son as he was. She had to wrestle with the same fears, uncertainties, and concerns that Abraham felt.

Out of her doubt and concern, she also determined a solution. Whereas Abraham proposed his solution to God, Sarah proposed her solution to Abraham. From Sarah’s perspective, she had no son because God had restrained her. Since God had restrained her, she would give Abraham her handmaid, Hagar. Hagar was to conceive a child in Sarah’s behalf. The child would then be reckoned as Sarah’s and could stand as their heir.

Sarah’s solution was not a device of her own imagination.² The practice of servants bearing children in behalf of their mistresses occurred in other families in the Bible, most notably with Jacob’s wives, Rachel and Leah (Gen. 30:1-24). Both the Nuzi Tablets and the Code of Hammurabi document the fact that Sarah’s proposal was an accepted practice in the culture of their former homes.

Sarah’s decision to provide an heir without God’s promised help proved to be no solution. A son, Ishmael, was born. However, Sarah was obsessed with jealousy of and resentment for Hagar from the time of Ishmael’s conception. The conflict became so unbearable that Hagar even attempted to run away.

Sarah’s doubt and concern produced results which distinctly differed from those of Abraham’s doubt and concern. Both Abraham and Sarah concluded that the promised son was not going to be born to them. Both concluded that God’s promises would go unfulfilled because of the lack of an heir. As both looked to the future, their deep concern turned into real doubt. Both felt that the situation still could be rescued if only they could provide an heir through which God could work. Both felt a personal responsibility to devise a means of acquiring an heir independent of God’s promise and action. Both found a personal solution to the problem which each felt was workable. However, Abraham’s doubt became faith upon God’s reassurance, and he abandoned his proposal. Sarah’s doubt produced a solution of her own making which resulted in her bitter jealousy and her harsh treatment of Hagar.

Ishmael was born to Abraham when he was 86 years of age. Thirteen years later at 99 years of age, Abraham received God’s confirmation that He indeed would establish His covenant with Abraham. On this occasion, God reaffirmed the covenant in specific terms. He would multiply Abraham exceedingly. He would make Abraham the father of a multitude of nations. Kings would descend from him. God’s covenant would extend to Abraham’s descendants who would inhabit Canaan as a continuing possession. God would be the God of Abraham’s descendants. As assurance, God renamed Abram “Abraham” (father of a multitude) and Sarai “Sarah” (Princess).

However, Abraham and his descendants must seal this covenant with God with a specific act: every male must be circumcised. Circumcision perpetually would stand as the sign of the covenant. Each descendant and each slave must be circumcised. The uncircumcised male would be cut off from Abraham’s descendants as a covenant violator.

Abraham never had doubted God to the degree which he did on this occasion. He fell on his face and laughed (v. 17). He asked in his heart, “Shall a child be born unto him that is a hundred years old? and shall Sarah, that is ninety years old, bear?” (v. 17). Then Abraham pleaded with God to accept Ishmael as his heir. Could doubt be any more complete? He laughed at the idea of their having a child. He declared it to be physically impossible. He regarded God’s promise as so impossible that he pleaded with God to accept one already born to him.

God’s reply was pointed and specific. Ishmael would not be the heir. Another son to be called Isaac would be born to him of Sarah. Sarah would give birth to Isaac at that same time in one year.

Please carefully note the faith which God reckons for righteousness. When God stopped talking with Abraham, Abraham immediately circumcised Ishmael, every male under his authority, and himself. Why? He placed his trust in God’s assurance. What had changed? Nothing. Was Sarah then pregnant? No, and she would not be for three months. What tangible evidence did Abraham have that God would do as He said? None. In the midst of consuming doubt Abraham believed God’s assurance when God renewed the promise.

Upon confidence in God’s promise alone, Abraham circumcised himself and every male under his control and oversight. Could there be any greater evidence of full trust in God’s promise? Could there be any greater affirmation of acceptance of the covenant? Circumcision is extremely painful. The resulting soreness lasts for days. It wounds one of the most sensitive parts of the human body. It was performed on that occasion (and for many generations after) with little to deaden the pain, little to disinfect the wound, and little to relieve the soreness. It was performed with crude cutting instruments. If grown men had to demonstrate trust in God today by subjecting themselves to such an ordeal, it is likely that the ranks of the church would diminish quickly.

Why did Abraham subject himself and all those men under him to such a painful ordeal? For one reason only: he believed that God would keep his promise. That kind of faith made Abraham righteous before God. It was not the obedience of being circumcised that made him righteous. It was the faith which prompted the circumcision which made him righteous.

1. Discuss God’s message to Abraham and Abraham’s response in Genesis 15.
   1. Why was Abraham concerned at this time?
   2. What was Abraham’s proposed solution?
   3. Where did he get such an idea?
2. What was God’s reaction to Abraham’s proposal?
3. Discuss the significance of Genesis 15:6.
4. Why had Sarah also been concerned?
5. What was her proposal?
   1. From her perspective, why had no son been born to her?
   2. Where did she get her solution?
   3. Did her solution work? Explain your answer.
6. Discuss God’s renewal of the covenant in Genesis 17.
   1. As an assurance, what did God do on this occasion?
   2. How much did Abraham doubt on this occasion?
7. How did God respond to Abraham’s doubt?
8. How did Abraham respond to God’s reassurance?
9. Discuss how Abraham’s faith reckoned for righteousness functioned on this occasion.

1. R. K. Harrison, Old Testament Times (Grand Rapids: Wm. B. Eerdmans Publishing Co., 1970), pp. 75, 76.

2. Ibid., p. 76.