Who against hope believed in hope, that he might become the father of many nations, according to that which was spoken,
So shall your descendants be.
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It is clear that since Abraham had no hope of having a son, he believed God and had faith against hope that he would have a son, knowing that with God all things are possible. The quotation is from Genesis [:], where God shows Abraham the stars of the sky and says: “So shall your descendants be,” because in believing he was justified. For Abraham believed what seems impossible to the world because it does not occur in the order of nature that old people should have children and know that their seed will increase to such an extent that it will be impossible to count them. Therefore, faith is precious because it believes in the future, even against what it now sees or knows. For it consoles itself in this hope, that it is God who promises. Commentary on Paul’s Epistles. ...
Who, against hope, believed in hope, or with hope. That is, Abraham, against all probability of human hopes, still hoped in God, says St. Chrysostom, that he should have a son by Sara: and in this, he was not weak in faith. Therefore it, that is, is great faith, was imputed to him unto justice: and also our faith shall be imputed to us unto justice, or make us truly just, by believing in Christ (Witham) ...