John the Baptist was in prison when he heard what Christ was doing, and he sent a message through his own disciples asking the question, “Are you the one who was to come or are we to look for somebody else?” (Matthew 11:2,3)
And I want to immediately address a false message that I've heard spoken about this moment: This is not doubt; this is not unbelief. Doubt and unbelief operate at the level of the Self: the mind and spirit of the doubter is almost always an echo-chamber where unanswered questions may harden into opposing beliefs.
In reality, John the Baptist, languishing in prison, gives us the perfect picture of what's to be done with our questions: externalize them... and only, first, in the direction of Jesus. Think of this: If between now and Matthew 14, when John will be beheaded by Herod's executioner, he had allowed this question no egress, no voice, he would've wasted every single moment remaining to him for the rest of his life; he wouldn't have gone to his death with the equanimity that I'm sure he did.
Cynicism, skepticism, doubt and unbelief are not virtues: they do not make you, or make you appear to be, intelligent. The true student approaches the True Teacher for instruction; the honest question-asker walks his wonderings toward the Answer Himself.
Do not dwell in your doubts. Go to Him. We must not waste a moment of our lives.