Imagine only being able to see 2 feet in front of you at any time. Now imagine not knowing that anyone could see farther than that. You think your eyesight is perfect.
Now a man walks up to you and says that he can see for miles, and that for him to take you to a good place, all you have to do is shut your eyes, take his hand, and follow him.
That is what Jesus asks us to do when he tells us to “Walk by faith, not by sight.” We ought to shut our pitifully weak eyes, and put our complete trust in the One who truly sees.