Romans 4:19-22

19Without becoming weak in faith he considered his own body, now as good as dead [for producing children] since he was about a hundred years old, and [he considered] the deadness of Sarah’s womb.

20But he did not doubt or waver in unbelief concerning the promise of God, but he grew strong and empowered by faith, giving glory to God,

21being fully convinced that God had the power to do what He had promised.

22Therefore his faith was credited to him as righteousness (right standing with God).