Humans are quick to doubt. We know this from experience. Here is an emotional scene. Jesus is weeping for His friend Lazarus. The crowd watching recognizes the great love that Jesus had for His friend, but it leads to a question. If He could heal the blind, why could He not have saved His friend?
This question comes from a heart of doubt. They refuse to see who Christ is, yet God is about to work a great miracle in the sight of these people to help them see who Jesus Christ really is. Compare this account to that of the Exodus. There are many similarities. There are hard hearted leaders, signs, and wonders. Jesus shows here that He holds the power of life and death. Christ will go on to be the Lamb foreshadowed in the Exodus, and all who believe will be saved by His blood.
Jesus worked these signs to His glory and so that His people would believe. Do you believe or do you doubt?
Consider: Psalm 78:18-20