Luke 7:18 And the disciples of John showed him of all these things.
They showed John who was in prison what Jesus was doing: the Centurions servant was healed and the dead man was raised to life. This should have encouraged this great prophet who had announced the coming of Jesus as the Lamb of God.
John 1:29 The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world.
John 1:30 This is he of whom I said, After me cometh a man which is preferred before me: for he was before me.
John 1:31 And I knew him not: but that he should be made manifest to Israel, therefore am I come baptizing with water. This is the one that John had said:
John 3:30 He must increase, but I must decrease.
John 3:31 He that cometh from above is above all: he that is of the earth is earthly, and speaketh of the earth: he that cometh from heaven is above all.
John 3:32 And what he hath seen and heard, that he testifieth; and no man receiveth his testimony.
John 3:33 He that hath received his testimony hath set to his seal that God is true.
John 3:34 For he whom God hath sent speaketh the words of God: for God giveth not the Spirit by measure unto him.
Luke 7:19 And John calling unto him two of his disciples sent them to Jesus, saying, Art thou he that should come? or look we for another?
Wow! How could this great prophet of God say this? A simple answer is that he himself was a man, not perfect who had doubts. One who had lived for years under the stars, living in the bright sun near the River Jordan, living off of the land. Being content in his calling. Now discouragement has set in. All was dark and he was in a filthy prison cell treated as an animal, because he spoke the truth. We can learn from this, that we too are flesh, subject to human emotions, but we must not forget the times when God spoke through us, first for salvation and then to follow him. John had spoken God's word, not his own. When we speak God's word, do we believe? Do we do what is says and above all have faith? John had lost the Spirit. Before Pentecost and the permanent giving of God's Spirit, the Spirit would come and go. John was in the flesh and in doubts when he asked this question.
Luke 7:20 When the men were come unto him, they said, John Baptist hath sent us unto thee, saying, Art thou he that should come? or look we for another?
Luke 7:21 And in that same hour he cured many of their infirmities and plagues, and of evil spirits; and unto many that were blind he gave sight.
Jesus was busy; healing, casting out demons, giving the blind sight. It is amazing that people still do not see when the Spirit of God is so evident. Jesus often was amazed at the lack of faith in his own disciples.
Luke 7:22 Then Jesus answering said unto them, Go your way, and tell John what things ye have seen and heard; how that the blind see, the lame walk, the lepers are cleansed, the deaf hear, the dead are raised, to the poor the gospel is preached.
Luke 7:23 And blessed is he, whosoever shall not be offended in me.
Jesus came to bless, but still there was and is unbelief. People get in their struggles with personal things, and loose sight of Jesus. Many are offended when we speak his name and his word. Atheists go to court to remove a cross from public land, they are offended in him. He cannot bless those who are offended with him with eternal life. John was confused, wanting to hear again the sweet words of Jesus, yes John, the very works that I do testify of me. Believe in me my friend. Keep believing and I will see you in Paradise.