Here is a remarkable miracle of our Lord. Surely there is no medicinal value in saliva, but the Lord uses this to increase the faith of this man. Why did He use this method? Couldn't He have opened the eyes of this man as He did in other instances? Of course, He could have. He could have made this man see clearly at the very beginning. But there is a lesson for the man and a lesson here for us.
There are three stages in this case:
1. Blindness. We are all first spiritually blind. Like the blind man we can say, "Once I was blind, but now I can see." But you'll notice that He gained only partial sight, and only Mark tells us this.
2. Partial sight. Is this not our condition today? "For now we see through a glass, darkly; but then face to face..." (1 Corinthians 13:12). Every now and then I get a letter from some person who gives me to understand that they have great spiritual discernment. But I have a confession to make to you. I only see through a glass darkly. There are many things I don't understand.
There are some people who don't feel that way. They think that they know all there is to know about everything. Socrates, in his day, made the statement that he was the wisest of the Athenians. That shocked everybody because he was a very humble man. So they asked him what he meant. And he said something like this, "Well there are a great many of the Athenians who think they know, and I know I do not know. And since I know that I do not know, I am the wisest of the Athenians."
May I say to you that there are a lot of the saints today who think they know. But Paul says that we see through a glass darkly, and that is our state in this life. But eventually when we come into His presence we shall know as we are known. I'll surely be glad when I get over there where I'm going to know something!
3. Perfect sight. The third stage is perfect vision. We'll get our 20/20 spiritual vision when we come into His presence, and that's when we'll really be able to see. You'll notice that when our Lord had finished, He had healed this man perfectly.
—From Edited Messages on Mark by J. Vernon McGee