Verse 20 says that he didn’t stagger at the promise of God through unbelief, but was strong in faith, giving glory to God. Verse 21 says that he was FULLY persuaded that what God had promised, he was able to perform. Abraham had no doubt in his mind at all about God and what He was able to do.
How about you today? Are you one of those people who finds it hard to believe God will do as He says he will? If you are, take an example from Abraham. What are you facing today that seems impossible in your life? Is there some situation that looks like there is no possible way out? Do you feel that this time there is no solution? If that is the way you are feeling, take heart. God will come through for you the same for you as he did for Abraham. He is a God of impossible situations. He can change anything.
God’s desire is that you trust Him regardless of how the situation may look in the natural. He will reward your faith and He will never disappoint you or let you down.