Look back at Matthew 3:1-17. John had been proclaiming the imminent coming of the one foretold by Isaiah. When Jesus had come to John to be baptized, at first John refused saying, "I need to be baptized by you," but agreed when Jesus assured him.
When John questions whether Jesus is the foretold Messiah, do we think that he wonders whether Jesus meets the expectations of what a messiah was supposed to do and be like, or do we think that he wonders whether they had the right expectations?
Jesus responded to the question about his identity by saying to John's disciples, "Go and tell him what you have witnessed, that the blind can see, the the lame can walk, the lepers are cleansed, the deaf can hear, and the poor have good news brought to them." Look at Isaiah 35 to see how this message would fulfill the prophecy.
What is it that we are expecting the Messiah to do for our world in our time? What signs would validate the identity of Christ for us? How concerned are we with other people's blindness, lameness, disease, etc.? Do we see the work of the Lord coming through those who care for the sick and the poor?