Romans 9:6-8 New King James Version (NKJV)
Israel’s Rejection and God’s Purpose
6 But it is not that the word of God has taken no effect. For they are not all Israel who are of Israel, 7 nor are they all children because they are the seed of Abraham; but, “In Isaac your seed shall be called.” 8 That is, those who are the children of the flesh, these are not the children of God; but the children of the promise are counted as the seed.
Romans 9:6-8 New International Version (NIV)
God’s Sovereign Choice
6 It is not as though God’s word had failed. For not all who are descended from Israel are Israel. 7 Nor because they are his descendants are they all Abraham’s children. On the contrary, “It is through Isaac that your offspring will be reckoned.”[a] 8 In other words, it is not the children by physical descent who are God’s children, but it is the children of the promise who are regarded as Abraham’s offspring.