Romans 4:20,21

He did not waver at the promise of God through unbelief, but was strengthened in faith, giving glory to God, and being fully convinced that what He had promised He was able to perform. 

Sometimes the only thing that stops the belief is lack of knowledge of what it says in the bible. We want to believe God will come through, but we haven’t taken the time to read the word and see what God says. Until we read the word and get revelation for our situation, we will stay stuck in unbelief.  Faith knows no matter what it looks like Gods’ word is true.