Abraham gave all that he had to Isaac because Isaac was the promised son of Sarah — the son with whom God said He would establish His covenant.
God had told Abraham that Sarah his wife would bear him a son and that he was to call the child Isaac. God then declared that He would establish His covenant with Isaac for an everlasting covenant (Genesis 17:19). Les Feldick emphasizes that Isaac — not Ishmael or Abraham's later sons — was the promised son through whom God's covenant purposes would continue, and Abraham acted on that by giving Isaac everything.
Genesis 25:5 — This verse records the very event behind the question — Abraham gave all that he had to Isaac.
Genesis 17:19 — This is the foundational promise explaining why Isaac was the heir: God said He would establish His covenant with Isaac, not with Abraham's other sons.
Genesis 22:2 — God's own words call Isaac Abraham's 'only son,' showing that in the covenant line Isaac was the unique heir.
The biblical record of the event is brief and explicit: 'And Abraham gave all that he had unto Isaac. But unto the sons of the concubines, which Abraham had, Abraham gave gifts, and sent them away from Isaac his son, while he yet lived, eastward, unto the east country' (Genesis 25:5-6). The reason for this singular act lies in the covenant promises God made before Isaac was born. God told Abraham, 'Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him' (Genesis 17:19). He had earlier said of Sarah, 'I will bless her, and give thee a son also of her' (Genesis 17:16). God's own words later confirmed Isaac's unique place: 'Take now thy son, thine only son Isaac, whom thou lovest...' (Genesis 22:2). And after Abraham's death, God appeared to Isaac and said, 'I will perform the oath which I sware unto Abraham thy father' (Genesis 26:3). Scripture thus presents Isaac not merely as a favored son, but as the sole heir of the covenant.
Les Feldick teaches that the key to the entire question is that Isaac was the promised son. He notes that in response to Isaac's promised birth, Abraham actually suggested Ishmael — 'O that Ishmael might live before thee' — but God refused and reiterated that Sarah would bear the son, who was to be named Isaac (Clips 1, 4, 6). Les stresses the significance of God's 'I will' as an unbreakable promise, making 'Isaac... a promised son' (Clip 1). At the same time, Les is careful to show that God did not reject Ishmael. God dealt with Ishmael as well, promising to make him fruitful, to multiply him exceedingly, and to make him a great nation (Clips 4, 5). But the covenant promises were not spread among all of Abraham's descendants — they were established specifically with Isaac (Clips 1, 4, 5, 6). Les also emphasizes that so far as God's covenant purposes were concerned, Isaac was Abraham's 'only son.' When God called Isaac 'thine only son,' Ishmael did not even count in that reckoning, because through Isaac would come the nation of Israel and the Messiah (Clip 7). He further notes that Abraham's later sons through Keturah produced peoples such as the Midianites, who became enemies of Israel — showing that the other branches of Abraham's family were outside the covenant line (Clip 0). Isaac alone is 'the true son of promise' to whom the covenant was referred (Clip 2). In the near-sacrifice of Isaac, Les sees a remarkable picture of this unique relationship: Isaac as a type of Christ, Abraham as a type of God the Father, and Abraham's faith that even if Isaac's life were taken, God would raise him up (Clip 3).
Yes. Abraham had Ishmael by Hagar, and at age 150 he married Keturah, and sons were born to her (Clip 0). But the covenant inheritance did not pass to them. God told Abraham that Sarah his wife would bear him a son, to be named Isaac, and that He would establish His covenant with Isaac (Clips 1, 4, 6). Les points out that Abraham's sons through Keturah produced peoples like the Midianites, whom he calls the 'arch enemies of Israel' (Clip 0).
Because, so far as God's covenant purpose was concerned, Ishmael did not even count as a son. Les explains that God was only concerned with Isaac, because through Isaac would come the nation of Israel and the Messiah (Clip 7). God's words in Genesis 22:2 — 'Take now thy son, thine only son Isaac, whom thou lovest' — make that unique place unmistakable.
No. Les emphasizes that God did not cast off Ishmael's people as nothing (Clip 4). In Genesis 17:20 God promised, 'I will make him fruitful, and multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation' (Clip 5). Yet the everlasting covenant was established with Isaac — not with Ishmael (Clip 5).
Abraham's Sons by Keturah — Outside the Covenant Line
Les shows that Abraham's sons through Keturah produced peoples such as the Midianites, whom he calls the arch enemies of Israel — demonstrating that the other branches of Abraham's family were outside the line of the covenant inheritance.
Isaac Becomes the Promised Son
When Abraham suggested Ishmael as the heir, God refused and promised that Sarah would bear Isaac. Les stresses that whenever God says 'I will' in Scripture it is a promise, and in that sense Isaac becomes the promised son.
Isaac — the True Son of Promise
After God made the covenant with Abraham, He referred it on to Isaac, whom Les calls 'the true son of promise.' The Lord appeared to Isaac just as He had to Abraham, confirming the covenant line.
Isaac as a Type of Christ
In the near-sacrifice of Isaac, Les sees Isaac as a type of Christ and Abraham as a type of God the Father, showing the same love relationship and sacrifice situation — and Abraham's faith that God would raise Isaac even from death.
The Covenant Established with Isaac, Not Ishmael
Les walks through Genesis 17:15-19: God changes Sarai's name to Sarah and promises a son of her. Abraham pleads, 'Why can't you use Ishmael?' but God answers that His covenant will be with Isaac — and He is not casting off Ishmael.
The Promise Is Valid — God Will Do It
Les emphasizes that God's promise to give Abraham and Sarah a son was valid despite their age because God said He would do it. God also dealt graciously with Ishmael, making him fruitful and a great nation — but the covenant promise remained with Isaac.
Abraham's Plea for Ishmael
Les explains that Abraham feared God would take Ishmael's life and pleaded, 'O that Ishmael might live before thee.' God's answer was the same promise: Sarah would bear Isaac and His covenant would be with him.
Isaac — the Only Son in God's Reckoning
Les notes that when God said 'take now thy son, thine only son Isaac,' Ishmael did not even count as a son in God's covenant reckoning — because through Isaac the nation of Israel and the Messiah would come.
Genesis 25:5: And Abraham gave all that he had unto Isaac.
The direct biblical record of Abraham giving his entire inheritance to Isaac.
Genesis 25:6: But unto the sons of the concubines, which Abraham had, Abraham gave gifts, and sent them away from Isaac his son, while he yet lived, eastward, unto the east country.
Shows that Abraham's other sons received only gifts, not the inheritance.
Genesis 17:19: And God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him.
God's explicit promise that the everlasting covenant would continue through Isaac.
Genesis 17:20: And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation.
God's blessing on Ishmael — a great nation, but not the covenant line.
Genesis 17:21: But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year.
Reinforces that the covenant belonged to Isaac, not Ishmael.
Genesis 22:2: And he said, Take now thy son, thine only son Isaac, whom thou lovest, and get thee into the land of Moriah; and offer him there for a burnt offering upon one of the mountains which I will tell thee of.
God's own words identifying Isaac as Abraham's only son in the line of promise.
Genesis 26:3: Sojourn in this land, and I will be with thee, and will bless thee; for unto thee, and unto thy seed, I will give all these countries, and I will perform the oath which I sware unto Abraham thy father;
God confirming the Abrahamic covenant to Isaac after Abraham's death.
Isaac was the son God specifically promised to Abraham and Sarah. God told Abraham to name the child Isaac and declared that He would establish His everlasting covenant with Isaac (Genesis 17:19). Abraham's other sons received gifts, but the entire inheritance — and the covenant line — went to Isaac.
Yes. God told Abraham, 'I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation' (Genesis 17:20). Les Feldick emphasizes that God never cast off Ishmael's people — they are just as eligible for salvation in this age of grace. But the everlasting covenant was established with Isaac, not Ishmael.
In God's covenant reckoning, Ishmael did not count as a son. Les Feldick explains that God was only concerned with Isaac because through Isaac the nation of Israel and the Messiah would come (Genesis 22:2). That is why Abraham could give everything to Isaac alone.
To the sons of the concubines Abraham gave gifts and sent them away from Isaac while he was still alive (Genesis 25:6). Les also notes that Abraham's sons through Keturah, such as Midian, produced peoples like the Midianites who became enemies of Israel. The inheritance itself belonged entirely to Isaac.
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