Why did God's promise come through Isaac and not Ishmael?
God’s promise came through Isaac rather than Ishmael because His purpose according to election was to stand, not of works or human deserving, but of Himself as the sovereign God who calls. The line of promise was therefore determined by divine choice, not by natural birth or merit.
Les explains that God made the promise through Abraham and Isaac, not Ishmael, so the next son of promise would come through that chosen line. He connects this to Rebecca’s twins, Esau and Jacob, who were not yet born and had done neither good nor evil, so that God’s purpose according to election might stand—not of works, not of what man deserves, but of Him who calls, the sovereign God. Les also illustrates that while “whosoever will may come,” the chosen were chosen from before the foundation of the world.
For this is the word of promise, At this time will I come, and Sarah shall have a son.
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