Finally they said, “Who are you? Give us an answer to take back to those who sent us. What do you say about yourself?”
John’s questioners needed to know who John was so they could report back to those who sent them, but John had denied every suggestion they had so far put forth so they changed tactics and asked John himself who he thought he was.
John was of priestly lineage but was not acting like a priest, so the priests and Levites were very interested in who he thought he was. He was acting like a prophet but there were many false prophets and it was the job of the Sanhedrin to make sure that prophets were really called by God and John did not conform to their image of what a prophet should be. He was different and new and that brought suspicion from the religious leaders. The church of today falls into that trap quite often. What preconceived ideas and doctrines are you unwilling to have challenged by the Lord?