“Neither because they are the seed of Abraham are they all children: but in Isaac shall thy seed be called.”
1611 King James Version (KJV)
9:7 Neither because they are lineally the seed of Abraham, will it follow that they are all children of God - This did not hold even in Abraham's own family; and much less in his remote descendants. But God then said, In Isaac shall thy seed be called - That is, Isaac, not Ishmael, shall be called thy seed; that seed to which the promise is made.
Ro 9:7 Neither, because they are the seed of Abraham, [are they] all children. Abraham had other children beside Isaac, notably Ishmael, but none of these belonged to the chosen people, for it was said, In Isaac shall thy seed be called. See Ge 21:12.