ACC ~ Romans 9 v9

THE SON PROMISED. AMBROSIASTER: This prefigures Christ, because Christ was promised to Abraham as a future son, in whom the word of the promise would be fulfilled. COMMENTARY ON PAUL’S EPISTLES.

SARAH SHALL HAVE A SON. CHRYSOSTOM: It is not the children of the flesh who are children of God, but rather even in nature regeneration through baptism from above was sketched out beforehand. … For Sarah’s womb was colder than any water, owing to barrenness and old age. … And just as in her case it happened when her age was past hope, so in this case also it was when the old age of sins had come upon us that Isaac suddenly sprang up in youth, and we all became the children of God and the seed of Abraham. HOMILIES ON ROMANS 16.

AUGUSTINE: This passage [to v. 29] is rather obscure. TO SIMPLICIAN ON VARIOUS QUESTIONS 1.2.1.

Rom