If asked to define faith, I’d probably give the most common textbook Christian response from Hebrews 11:1: Faith is being sure of what we hope for and certain of what we do not see.

Lately I’ve been thinking about what that statement means practically. A few days ago, I read the story of Jesus healing the blind man in John 9 and saw a practical example. We don’t know much background about the blind man—just that he is a beggar who was blind from birth. All we’re told is that Jesus sees the man and his disciples ask if he is blind because he or his parents had sinned. Jesus responds that he isn’t blind because of sin; he is blind so that the work of God might be displayed in his life.

Then Jesus spits on the ground and mixes his saliva with dirt to make mud. It must have taken a lot of spit to make enough mud, because Jesus then picks up a handful and wipes it on the blind man’s eyes. Maybe it’s just me, but if I was the blind man, I think I’d be a little annoyed at this point. Presumably, I’d be worse off than before. Not only am I still blind, but now I have a smelly mixture of dirt and spit on my face.

Jesus then tells the man, “Go, wash in the Pool of Siloam.” We’re told that Siloam means Sent. This is where the blind man’s faith comes into action. He is sent on a journey of faith. He hopes he’ll regain his sight by doing what Jesus says, but how does he know for sure?

We’re not told what he says or how he gets to Siloam—just that he goes and washes and comes home seeing. When he gets back, his neighbors are surprised and ask him how his eyes were opened. His response is simple enough: “The man they call Jesus made some mud and put it on my eyes. He told me to go to Siloam and wash. So I went and washed, and then I could see.”

I think there’s a lot we can learn from the blind man. He demonstrated his faith in a practical way. He simply did what Jesus told him to do and trusted that it would be worth it. He was sure of what he hoped for and certain of what he did not see.