Romans 4:18-21 NIV

[18] Against all hope, Abraham in hope believed and so became the father of many nations, just as it had been said to him, “So shall your offspring be.” [19] Without weakening in his faith, he faced the fact that his body was as good as dead—since he was about a hundred years old—and that Sarah’s womb was also dead. [20] Yet he did not waver through unbelief regarding the promise of God, but was strengthened in his faith and gave glory to God, [21] being fully persuaded that God had power to do what he had promised.