The literary division of Genesis along the lines of generations (Heb. toledot) goes from 25:19 until the end of ch. 35, but narratively the focus shifts at 28:10 from Isaac and his immediate family to his son Jacob in particular.  In the Genesis narrative, the account of Jacob provides the pivotal connection between the patriarchal period and the Exodus generation, since it is with Jacob that the people of God go from being just a family to being a nation.  It was Jacob’s family that would go into Egypt during the famine; it would be the nation of Israel that would come out in the Exodus.  Nevertheless, although Genesis gives greater attention to Jacob—almost half of the book—the short account of Isaac is still important in showing how God’s covenant promises were conveyed to Jacob.  Three themes related to the covenant can be discerned in chapters 23 to 28: (1) How God protected the promised seed of Abraham; (2) The continual need for covenantal love to the LORD, shown negatively by the failures of His people; (3) How God extended and confirmed His covenantal promises to His people nonetheless.

The continuation and protection of the chosen seed.  Much of the Abrahamic narrative is focused on the coming of an heir through whom God’s covenant promises would be conveyed, and that heir was Isaac.  Once Isaac was born and especially in his brush with almost being sacrificed, God’s protecting hand remained upon him.  That protection continued in his life and conveyed to his son Jacob.  The godly seed risked being lost because of intermarriage with the pagan nations amongst whom Isaac and his family lived.  Abraham probably recognized this, which was why he was adamant that his son neither marry into the Canaanites nor return to the land of Haran which Abraham left.  The beautiful account in Genesis ch. 24 of Abraham’s servant finding Rebekah, a wife for Isaac, shows God’s providential working through the entire episode.  Rebekah, like Sarah before her, was barren until the LORD opened her womb with twins.  The sovereignty of the LORD was evident in His revelation that the older child would serve the younger (25:23), a pattern that God would follow repeatedly throughout the remainder of biblical history.  God intervened when Isaac was in Gerar, to prevent another Abimelech from taking Rebekah into his harem given that Isaac followed his father’s sinful pattern of declaring her to be his sister, not his wife (26:6-11).  The risk to the godly line was highlighted in the narrative by the negative example of Esau (26:34-35).  Esau’s direct threat to Jacob, through whom God’s promise would come, was thwarted by Rebekah’s justification desire that Jacob not succumb to marrying women of the land but to find a wife from among her own family (27:46-28:5).

The continuing need for covenantal faithfulness.  Isaac and his family, like Abraham, had to learn covenantal faithfulness.  Despite God’s deliverances of Isaac, Isaac still trusted in his own connivance when he was in Gerar, rather than in the protection of the LORD (26:9).  Moreover, even though Rebekah had been told that of her sons, the older would serve the younger, Isaac favored Esau over Jacob for little more than personal reasons (25:27-28).  Esau, in fact, was indifferent to the covenant promises of God, as evident in how he despised his birthright (25:29-34).  Rebekah and Jacob were not much better than Isaac, in that while they did value the promises of God, they sought to attain those promises through their own efforts, rather than in trusting in God.  This is clearly displayed in the deception that they exercise toward Isaac to secure his patriarchal blessing for Jacob (27:1-29).  Jacob, in his experience of fleeing to and then twenty years later returning from Padan Aram would be the only one who would develop the kind of covenantal faithfulness that his grandfather Abraham exhibited, as would be seen in subsequent chapters.

The extension and confirmation of God’s promises.  Despite this lack of covenantal loyalty, within these chapters one sees the echoes of God’s covenant promise is in the blessing that Rebekah’s family gave her as she left to become Isaac’s wife (24:60).  The LORD extends the covenant promise to Isaac during a famine, when he tells Isaac to stay in the land despite the famine, and that in so doing and in keeping God’s statutes and laws as Abraham had done, He would multiply Isaac’s offspring and bless the nations of the world through him (26:1-5).  This harkens back to God’s original promise to Abraham in 12:1-3.  The most obvious extension of God’s promises is in Jacob’s acquisition of the birthright of the firstborn (25:29-34) and then in Isaac’s subsequent blessing upon Jacob (27:27-29).  The writer of the epistle of the Hebrews points to this sole act as the justification for including Isaac in the testimonies of faith (Heb. 11:20).  Less obvious but also important are certain acts that help secure the patriarch’s legal claims to the land.  This is the significance of the covenants Abraham and Isaac made with the Abimelechs (21:22-34 and 26:12-33), as well as the extensive discussion of why Abraham bought the land from Ephron the Hittite to bury Sarah (ch. 23).  These transactions established a legal basis for Abraham and Isaac to the land, and such legal recognition was an indirect confirmation that God’s promise to give Abraham’s offspring would be fulfilled.

There are multiple episodes in the development of God’s covenant with Abraham, but they should be treated as all part of one covenant.  In international diplomacy, the sum total of multiple agreements between two covenant-making parties—larger agreements and smaller ones, formal and informal, and precedents set in the history of relations between two parties—is known as a “treaty regime.”  This is important to recognize because there is a tendency oftentimes to view things in a reductionist manner, for example, separating God’s promise in 12:1-3 from the covenant-making ceremony in ch. 15, and that from the sign and confirmation of the covenant in chs. 17 and 22.  Such reductionism lends itself to seeing the separate events as potentially contradictory, rather than as building upon each other.  What we see here in chs. 12-17 (and really, through ch. 22) is the development of God’s covenantal regime with Abraham, and this is at the core of God forming a people for Himself.  The Apostle Paul, in his letter to the Galatians, saw a continuity between the promises given to Abraham and those under the Mosaic covenant which would come 430 years later (Gal. 3:15-18).

God’s promises to Abraham in 12:1-3 are foundational to the Abrahamic covenant, even though the actual covenant-making ceremony does not come until ch. 15.  God gives Abraham a command to leave his country and family and travel to a land He will show him, so as to be wholly committed to the LORD.  The imperative comes with three promises: (1) God will make Abraham a great nation (v. 12:2a); (2) He will bless Abraham personally and make his name great (12:2b); (3) He will make Abram a blessing to all the families of the world, blessing those who bless him and cursing those who curse him (12:2c-3).  The third promise is the means by which the first two promises will come to fruition.  The narratives that follow up to ch. 15 show the beginning of the fulfillment of that promise.  Despite Abraham’s lack of faith while in Egypt, for example, even Pharaoh realizes that he would receive a curse if he took Abraham’s wife Sarah into his harem, and instead sends Abraham and Sarah away with a blessing (12:10-17).  The separation of Abram and Lot and Abram’s subsequent rescue of Lot in chs. 13-14 shows not only Abraham’s growing greatness and blessing, but also how others benefit from that blessing (e.g. Lot) or seek it (e.g. the king of Sodom).  Abraham’s interaction with Melchizedek, the king of Salem, shows that Abraham is fully aware of the fact that the blessing he has received comes from the LORD alone (14:18-24).  In the New Testament, the writer of the letter to the Hebrews, drawing on this passage and Psalm 110:4, recognizes Melchizedek as a foreshadowing of One who is both a king and a priest of God Most High, namely Christ Jesus Himself (Heb. 5:5-11).  The Seed of Abraham would be the One who would bless all the families of the world.

The account of Abraham reaches its climax with his testing in ch. 22, and the narrative arc of chapters 12-22 revolve around the theme of God producing a seed through whom Abraham and the world would be blessed, while at the same time building Abraham’s faith and covenantal loyalty to God Himself.  The focal point of these chapters is the covenant-making ceremony in ch. 15.  The dialogue between God and Abraham preceding (indeed, prompting) the ceremony itself is rather curious and needs to be read closely and carefully.  The LORD states that He Himself is Abraham’s inheritance (15:1), that is, communion with Him is Abraham’s ultimate reward.  This touches off a dialogue about what inheritance actually entails, revolving around heirs and land, since Abraham has no naturally-born children and, despite having sizable flocks and herds, has been nomadic, not actually possessing any land.  Harkening back to His promise to Abraham in 12:1-3 and even to Eve in 3:15, the LORD underscores His promise of a specific offspring from Abraham and the multitude that would come from that seed (15:4-5).  Abraham accepts this by faith.  Echoing 12:1 and 13:14-17, the LORD then reiterates the promise of the land.  It is at that point that Abraham asks for assurance that this will indeed come to pass, which results in the covenant-making ceremony.

It is vital to recognize that the land promise was always intertwined with and subordinate to the promise of a people, and that the promise of a people was not an end in itself, but was subordinate to ultimate communion with God.  God’s promise to Abraham that “I am your shield, your exceedingly great reward” (15:1) is a promise to us as well as the spiritual heirs of Abraham.  The first question of both the Westminster Larger and Shorter Catechisms capture this sentiment in declaring that “The chief end of man is to glorify God and enjoy Him forever.”  Keeping this in mind properly contextualizes the land promise, since some Christians get too focused on specific territory occupied now by the state of Israel, while others try to draw too fine a distinction between God’s promises of a people and His promises of the land.  In this ancient world it was common for a suzerain king to gift lands to faithful vassals as a reward for their faithfulness.  It was widely understood that such grants were implicitly conditional in that the vassals could retain those lands only insofar as they remained faithful; if they became unfaithful, the land grant could and probably would be revoked.  The land promise, therefore, has a threefold significance: (1) it is a reward for Abraham’s faith in trusting God’s promise of a people; (2) it is a down payment on the promise of a people; and (3) it would be a place where God’s would have communion with that people.  The terms of the covenant are focused on God redeeming a people for Himself (15:13-16).  Later in the biblical narrative it will be shown that the LORD did redeem Abraham’s seed in the Exodus and give them the land, but because of their unfaithfulness their right to dwell in the land was revoked.  God’s promise of a people redeemed to Himself, however, remains constant throughout Scripture.  Our communion with Him now is not in the land, but through His Holy Spirit.

The formality of the covenant was a solemn legal assurance to Abraham of God’s promises.  The covenant-making ceremony of Genesis 15 is an archetypal example of such a ceremony, albeit with an important twist.  In making a covenant, the two parties would take a number of sacrificial animals, divide them in two, and lay them on opposite sides of a short pathway.  The titles of the two parties would be declared, with whatever preambular declaration was appropriate summarizing the state of their relations to that point.  In this case, only the LORD’s title is given: “I am the LORD that brought you out of Ur of the Chaldeans, to give you this land to inherit it” (15:7).  The terms of the covenant would then be stated specifying the obligations of the two sides, and then they would swear an oath, with the gods as their witnesses, and proceed to walk down the pathway of the slain animals.  Symbolically, the slain animals represented the self-maledictory curses of the covenant; the parties were saying in effect “May the gods do unto us as we have done to these animals—divided and dismembered—if we violate this covenant.”  It is from this symbolism that the Hebrew phrase for “making a covenant” literally means, “to cut a covenant.”  The twist with this particular ceremony, however, is that it is only God Himself—as represented by the smoking oven and flaming torch—that passes between the slain animals (15:17).  In this, God is saying that for any violation of the covenant by either side, He alone will absorb the curse of the covenant.  While the LORD cannot and will not violate the covenant because He is perfect and unchanging, for the sins of the people He will take on death.  This is an amazing act of grace that ultimately would be fulfilled in the Person and Work of Christ Jesus.

Although Abraham believed that the LORD would provide Him with offspring and give him the land as an inheritance, he still needed to learn that God would supply the means to those ends.  This is the narrative arc of Genesis chs. 16-22.  Abraham and Sarah tried to grasp the promise through their own efforts in ch. 16, when Abraham took Sarah’s handmaid Hagar and fathered a child by her, Ishmael.  The LORD made it clear, however, that he is not the child through whom God’s covenant promises will be fulfilled.  God renewed His covenantal vows in  17:1-8, telling Abraham that the promised seed will be a son named Isaac, which Sarah will bear a year hence (17:15-21).  He stipulated that as part of the covenant the male children and menfolk within Abraham’s house would need to circumcised, which Abraham readily did (17:9-14, 23-27).  A few months later, the LORD, in the form of three mysterious men, appeared and reiterated the promise that Sarah will bear the promised son, Isaac.  More than that, the LORD takes Abraham into His confidence to reveal to him His plan to bring judgment upon Sodom.  In the exchange that followed as Abraham essentially bargained for the lives of his nephew Lot and his family, Abraham learned the character of the God whom He served, that the LORD was righteous, just and merciful, as well as powerful (ch.18).  Lot’s negative example and sorry end in ch. 19 highlighted the importance of God’s people being covenantally consecrated to the LORD, rather than co-opted and conformed to the world.  Shortly thereafter, Abraham and his household relocates to Gerar and he once again stumbles in his faith, trying to secure his safety from the local king Abimelech by claiming that Sarah is his sister (ch. 20).  Had this not been checked by the LORD, it would have brought into question the legitimacy of Isaac’s parentage (and hence, God’s promise) had Abimelech took Sarah into his harem.  When Isaac finally is born, God further preserves the life of Isaac by moving Sarah to send Hagar and Ishmael away, lest Ishmael become a threat to Isaac (21:8-21).

Through all these experiences, Abraham not only grew in faith in trusting the LORD, but grew in covenantal love to the LORD.  The term for this in the Old Testament is hesed, and the richness of the concept does not translate neatly into English.  Hesed is the term used most often in the Old Testament for love and goes well beyond our contemporary connotations of the notion of love.  Translators of the Bible have used terms like “lovingkindness,” “steadfast love,” or “mercy” to try and capture the concept.  In a covenantal framework, a suzerain would expect his vassal to grow in loyalty, trust, faithfulness, and devotion to him over time.  It is not a sentimental love per se, although that may be present.  Rather, it is a steadfast, sacrificial, persevering devotion that exists and persists regardless of circumstances.  The concept underlies the ultimate call to God’s people in Scripture in Deut. 6:4-5: “Hear, O Israel: The LORD our God, the LORD is one!  You shall love the LORD your God with all your heart, with all your soul, and with all your strength.”  Christ identifies this as greatest commandment in Mark 12:29-30 and Luke 10:27.  Abraham learned hesed, so much so that when God puts him to the test in Gen. ch. 22 and asks him to sacrifice this long-desired son who would fulfill God’s covenant, his willingness to do so was not a blind leap of faith.  Rather, Abraham had seen God’s faithfulness and hesed throughout the years, even when he himself lacked faith, and consequently he believed that God would do something to save Isaac.  Hence, the writer to the Hebrews can say, “By faith Abraham, when he was tested, offered up Isaac, and he who had received the promises offered up his only begotten son, of whom it was said, ‘In Isaac your seed shall be called,’ concluding that God was able to raise him up, even from the dead, from which he also received him in a figurative sense” (Heb. 11:17-19).  Isaac was the seed through whom the promise would come, but also pointed to Christ, who would be offered up by God for the sins of the world and literally raised from the dead afterwards.  The hesed of Abraham is the same hesed God’s people are called to.