Why are not all the descendants of Abraham children of the promise?
Because God's covenant promise was not established through every physical descendant, but specifically through Isaac, whom Sarah would bear at the set time, and then through Jacob and the twelve tribes. Ishmael received blessings and became a great nation, yet the covenant line of promise ran through Isaac, not Ishmael.
Les explains that Ishmael was Abraham’s son and God blessed him, promising to make him fruitful, multiply him exceedingly, give him twelve princes, and make him a great nation. But God said His covenant would be established with Isaac, whom Sarah would bear at the set time. Thus, not all Abraham’s children are children of the promise; only those coming through Isaac and Jacob and the twelve tribes. The Arab peoples were blessed and multiplied, but the covenant promise ran through Isaac’s line, not Ishmael’s.
Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called.
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