a. Now faith is the substance: Just as our physical eyesight is the sense that gives us evidence of the material world, faith is the “sense” that gives us evidence of the invisible, spiritual world. i. Faith has its reasons. The Bible doesn’t recommend a “blind leap” of faith. But the reasons can’t be measured in a laboratory; they have to be understood spiritually. “Faith extends beyond what we learn from our senses, and the author is saying that it has its reasons.