In the physical realm we know much about health issues like cholesterol, smoking, and obesity, but the medical community has no cure for these problems beyond people changing their behavior. Faith is probably best understood when we see it in the lives of great men.
Bible truths become clearer when they breathe.
Abraham was called the father of the faithful because in him faith came to life. Abraham had faith in a God-given vision. That's the kind of faith that is important. The vision that God gave Abraham was so big that it challenged him for a lifetime. God's vision for Abraham's life was the motivating factor that made Abraham a great man.