Romans 4:20-21 No unbelief made him waver concerning the promise of God, but he grew strong in his faith as he gave glory to God, 21 fully convinced that God was able to do what he had promised.
Abraham stayed true to the promise. He struggled with how God would fulfill the promise, for example with Sarai in Egypt and then with Hagar the Egyptian slave. Paul may not be thinking of these situations in his mind but considering the overall story of how God fulfilled the promise of many descendants. The important link is between growing stronger in faith and giving glory to God. That is the key to strong faith. Sin is just the opposite: failing to glorify God and replacing worship of God with created things (Romans 1:23). Verse 21 is a good definition of faith: being fully convinced that God will do what he has promised. It takes faith to believe in an invisible God, even though evidence of his existence is plain for those with honest and open minds. Circumstances and challenges of life raise doubts and questions. Doubt and questions can chip away at our faith. Abraham gives us a good example of not wavering but holding true to the course marked out for us. Paul is focusing particularly on faith in Jesus that brings justification and sanctification.
For older posts, click here.