The brevity of this text belies its theological weight: in just six verses, we have messages about the reliability and timing of God’s promises, lessons about prayer, and a verse so packed with import that it is quoted in two New Testament passages as a lynchpin for understanding the relationship between faith and works.
Even though the entire chapter is worth considering for the way it illustrates the way that God makes (literally, “cuts”) a covenant, this pericope will offer plenty of material for a preacher to utilize.
Verse 1 begins with a reference to some previous things, most likely the immediately preceding chapter. God’s word appears to Abram in a vision, reminiscent of the way that the prophets both hear and see God’s message (cf. Amos 1:1). The first thing Abram is told is not to fear, and continues by telling Abram that God will be his shield, words that must have been more reassuring after Abram had just been involved in battle to rescue Lot (Genesis 14: 14-15).
God also tells Abram that Abram’s reward (literally, his “wages” or “pay”) will be exceedingly great. This, too, connects with what has come before; when the king of Sodom told Abram to keep some of the goods from battle, Abram refused any of his commodities. The KJV translates the “reward” as God, such that God tells Abram, “I am thy shield, and thy exceeding great reward.”
Abram’s response to this revelation, however, is not one of gratitude. Rather, he asks a question that essentially amounts to, “What is my reward?” If the reward has been unspecified, this is a good question; if the reward is God, as KJV suggests, this is an even better, albeit bolder, question. Within these verses, Abram wants to know who God is, and how God can be trusted, particularly when there has been a delay between God’s promise and its fulfillment. Another paraphrase for Abram’s question in verse 2 is, “Really?” That question could be expressed in a tone of disbelief, or genuine curiosity, or some mixture of the two. God had promised descendants, but they have yet to be made real, so perhaps Abram is asking, “What will you give me? Is my reward to be something other than children?”
Verse 3 begins exactly the same way as verse 2, with the phrase “and Abram said.” It is as if after Abram first posed his question to God in verse 2, he does not leave any time for God to respond before Abram says something else. The urgency in Abram’s discourse points to the importance of Abram’s questions and concerns, as if he can’t wait to express them to God. Abram’s statement in verse 3 is less ambiguous than his question in the preceding verse. The only one poised to be his heir is this Eliezer of Damascus, who is only a servant.
Additionally, it is clear that Abram holds God responsible for his lack of an heir: “Look, you have not given children to me” (literally, “seed”). God’s promise to Abram has yet to come true. And yet, Abram must have a level of faith to even register disappointment that God has not yet done what God said God would do. That is, Abram expects -- and believes -- God will keep God’s word, which is why Abram speaks in the way he does.
God’s response is direct and reassuring: “This man will not be your heir, but rather one who will come from your body (Hebrew: ‘loins’) will be your heir.” Thus, God reiterates that Abram will have descendants and specifies that those descendents will be biological. But the reiteration and specification still requires trust, as God does not give Abram a date or time for this happening. It will not be until Genesis 17:21 when God tells Abraham that Sarah will bear him a son in a year. Though that is only two chapters later, it is at least thirteen years after God told Abram he would have a biological son, making it at least fourteen years before God delivers on this promise.
In verse 5, God adds a visual to the promise. Abram is told to look to the night stars and count them if he is able, that his descendants will be that numerous. In the ancient desert, the number of stars must have been staggering; he must have been able to see the swath of the Milky Way. In the years left to wait between this word and the fulfillment in Isaac’s birth, Abraham must have been bolstered when he saw the night sky and remembered this word.
The final verse of this selection contains Abram’s response: he believed in the Lord. The second clause, however, is ambiguous as to the subject and object. Most English translations preserve the ambiguity, “he reckoned it to him as righteousness.” Is God the one reckoning, or is Abram? Those translations that capitalize the pronouns for God write, “and He reckoned it to him as righteousness,” and the NRSV clarifies, “and the Lord reckoned it to him as righteousness.”
The Hebrew, however, could just as well mean that Abram’s belief led to Abram reckoning it to God as righteousness. The verb “reckon” can also be translated as “think, account, impute.” If Abram is the object, and God is the subject, this would mean that Abram thought of God as righteous, imputed righteousness to God. Now, that may sound audacious: how can a human impute or reckon righteousness to God? Or, it may seem patently obvious; of course God is all righteousness, why does it matter if Abram thinks so or not?
However, the heart of this interaction is faith and trust. If Abram understands God to be righteous, to be one whose word is firm and secure, to be one who will make good on God’s promises, then Abram can believe. The same is true for us. Belief is hard enough when there is a delay between God’s promises and their fulfillment. It would be nigh impossible if the God in whom we believe is not trustworthy, is not righteous.
 Genesis 16:16 tells us that Abram was eighty-six when Ishmael was born, and Genesis 17:1 tells us that God (re)appeared to Abram when he was ninety-nine. If chapter 16 immediately follows chapter 15, it was still thirteen years before Abram got the message (in chapter 17) that he was to have a son with Sarah within a year.