Romans 4:18

Against all hope, Abraham in hope believed and so became the father of many nations, just as he had been told, “So shall your offspring be.”

Note Genesis 15:5

BSB · Berean Standard Bible
Who against hope believed in hope, that he might become the father of many nations; according to that which was spoken, So shall thy seed be.
KJV · King James Version
Against hope, Abraham in hope believed, to the end that he might become a father of many nations, according to that which had been spoken, “So will your offspring be.”
WEB · World English Bible
Who in hope believed against hope, to the end that he might become a father of many nations, according to that which had been spoken, So shall thy seed be.
ASV · American Standard Version

Related passages

From the Treasury of Scripture Knowledge, grouped by the word they explain.

against
Romans 4:19; Romans 5:5; Romans 8:24; Ruth 1:11–13; Proverbs 13:12; Ezekiel 37:11; Mark 5:35, 36; Luke 1:18; Acts 27:25
So shall
Genesis 15:5, 6