We are first challenged from this passage to examine how well we are obeying Christ. The 12, armed with the instructions they had just received, went out immediately as they were commanded to do the work of Christ.
We see that unbelievers, of necessity, cannot have a true view of Christ. Because of unbelief, they have all manner of wrong or deficient ideas about Him.
This passage shows us that this may also happen to believers from time to time as their indwelling sin rears its ugly head. They can begin to doubt that Christ is who He says He is, not to see Him in all His glory.
This is what happened to John the Baptist. Perhaps Christ was not matching up to his expectations of Messiah. John may have been in prison now for a year and was suffering - his faith was being buffeted by the trials he was enduring.
Christ points John to the fact that He was doing what the prophets said Messiah would do - and that the outward things He was doing were indicative of deeper, inward works that were also taking place.
We are all exhorted not to stumble over this Christ - either as believers, for then we shall accomplish little for Him, or as unbelievers, for then we shall surely perish. The answer for all these spiritual ills is to come to Christ, the Great Physician of souls, for He alone can heal.