Theophylact of Ohrid
Catena Aurea · Lukasevangelium 20
And it came to pass, that on one of those days, as he taught the people in the temple, and preached the Gospel, the Chief Priests and the Scribes came upon him with the elders, And spake unto him, saying, Tell us, by what authority doest thou these things? or who is he that gave thee this authority? And he answered and said unto them, I will also ask you one thing; and answer me: The baptism of John, was it from heaven, or of men? And they reasoned with themselves, saying, If we shall say, From heaven; he will say, Why then believed ye him not? But and if we say, Of men; all the people will stone us: for they be persuaded that John was a prophet. And they answered, that they could not tell whence it was. And Jesus said unto them, Neither tell I you by what authority I do these things.
For that He might shew that they had always rebelled against the Holy Spirit, and that besides Isaiah, whom they remembered not, they had refused to believe John whom they had lately seen; He now in his turn puts the question to them, proving that if so great a Prophet as John who was accounted greatest among them had been disbelieved when he testified of Him, they would in no wise believe Him, answering by what authority He did this.