11:2 When John had heard in the prison. Compare Mr 6:14-29 Lu 7:19-28. John had now been a year in prison, to which he had been sent by Herod Antipas, the tetrarch of Galilee, because he had rebuked his adulterous marriage with his brother Philip's wife (Mt 14:1-11). Josephus says that Machaerus, a strong fortress built by Herod the Great, the father of Antipas, about ten miles east of the Dead Sea, was the prison.
He sent two of his disciples. To make the inquiry found in the next verse. The course of Jesus was so different from what John himself, in common with other Jews, expected of the Messiah, that after lying in a dungeon for a year, he began to be uncertain. If Jesus was the Christ, why did he not proclaim himself the Messiah King, destroy the power of the Romans and of Herod, and release John himself from prison? So he reasoned.
11:2 He sent two of his disciples - Not because he doubted himself; but to confirm their faith. Luke 7:18.
11:2-6 Some think that John sent this inquiry for his own satisfaction. Where there is true faith, yet there may be a mixture of unbelief. The remaining unbelief of good men may sometimes, in an hour of temptation; call in question the most important truths. But we hope that John's faith did not fail in this matter, and that he only desired to have it strengthened and confirmed. Others think that John sent his disciples to Christ for their satisfaction. Christ points them to what they heard and saw. Christ's gracious condescensions and compassions to the poor, show that it was he that should bring to the world the tender mercies of our God. Those things which men see and hear, if compared with the Scriptures, direct in what way salvation is to be found. It is difficult to conquer prejudices, and dangerous not to conquer them; but those who believe in Christ, their faith will be found so much the more to praise, and honour, and glory.