Luke 7:27
This is he, of whom it is written, Behold, I send my messenger before thy face, which shall prepare thy way before thee. This is he, of whom it is written, Behold, I send my messenger before thy face, which shall prepare thy way before thee.
This is he of whom it is written identifies John the Baptist as the promised messenger sent ahead to prepare the way for Christ. He is more than a prophet because he is that promised messenger. He was the connecting link between the two dispensations, a lesser light preceding the greater light of Christ.
His appointed work was to recall people to their sins, call sinners to repentance, and prepare people to receive Christ. His ministry heralded Christ's kingdom. Part of that preparation was to loosen confidence in human traditions so people could recognize Christ's work.
The fact that publicans and harlots accepted his message showed that God had authorized his mission. His faithful preaching included calling Herod to repentance and denouncing his unlawful marriage to Herodias, which brought about John's imprisonment. His plain dress and self-denying life suited his mission to reprove the sins and excesses of his time, in contrast to priests and rulers in rich robes and costly ornaments who sought display and human admiration and served the kingdom of this world.
Although many hoped John was the Messiah, his mission was to direct people to the coming One. He refused honor for himself before the Sanhedrim, the people, and his own disciples, pointed all to Jesus as the Promised One, and rejoiced unselfishly in Christ's ministry. His greatness in Heaven's sight came not from wealth, rank, descent, or intellect alone but from moral worth, love, and purity. He expected the Messiah to take David's throne, overthrow oppressors, and bring judgment, so Christ's ministry of teaching and healing did not match his expectation.