What is belief without faith? The answer is there really no good without each other.
Belief is knowledge and believing what we know.
Faith is acting on that belief even though the world says otherwise.
So why is something so simple so hard to use? Because there is a conflict, a conflict between what we see and what we don't.
Since we live our lives based on senses such as sight, smell, touch and hearing, faith is just the opposite.
If God says were healed and the Doctor says were not, there's a large tumor in your body, what do we believe?
This is the conflict.
Sin Doesn't Help
This is where sin does it's best work.
Sin knows how hard it is for us to put both faith and belief together. It will give up one to attack us with the other. Not only do we not get what God promises us, but we allow doubt to confuse us even more.
You might say "I believe Gods words but he didn't heal me, what happened?" You have to ask yourself, "What action of faith did you take?"
Faith starts with thoughts, did you worry? Do you have fear? Is anxiety part of your feelings?
These are products of sin and they short circuit faith. So sin will gladly give you belief as long as he can shake your faith.