Romans 9:6-8

YLT(i) 6 And it is not possible that the word of God hath failed; for not all who are of Israel are these Israel; 7 nor because they are seed of Abraham are all children, but—`in Isaac shall a seed be called to thee;' 8 that is, the children of the flesh—these are not children of God; but the children of the promise are reckoned for seed;