The writer of Hebrews highlights the faith of Abraham (He. 11:8-10, 17-19), and Paul uses Abraham’s faith as an example of how our faith is credited as
righteousness (Ro. 4).
The key to Abraham’s faith is the statement, “…with respect to the promise of God, he did not waver in unbelief, but grew strong in faith…being fully assured that what God has promised, He was able also to perform” (Ro. 4:20-21).
The example of an unwavering faith points to our confidence and relationship with God. Doubt is eliminated and certainty in God’s promise is promoted.