John Calvin on Genesis 18:10

10. I will certainly return unto thee Jerome translates its ‘I will return, life attending me:’ “Vita comite revertar.” See Vulgate , where the expression is “Revertens veniam ad to tempore illo, vita comite.” as if God, speaking in the manner of men, had said, ‘I will return if I live.’ But it would be absurd, that God, who here so magnificently proclaims his power, should borrow from man a form of speech which would suppose him to be mortal. What majesty, I pray, would this remarkable oracle possess, which treats of the eternal salvation of the world? That interpretation, therefore, can by no means be approved, which entirely enervates the force and authority of the promise. Literally it is, according to the time of life. Which some expound of Sarah; as if the angel had said, Sarah shall survive to that period. But it is more properly explained of the child; for God promises that He will come, at the just and proper time of bringing forth, that Sarah might become the mother of a living child.