and they said to him, “By what authority are you doing these things, or who gave you this authority to do them?”
We have here Christ examined by the great Sanhedrim concerning his authority; for they claimed a power to call prophets to an account concerning their mission. They came to him when he was walking in the temple, not for his diversion, but teaching the people, first one company and then another. The Peripatetic philosophers were so called from the custom they had of walking when they taught.
Commenting on Mark 11:27-33
And Jesus answered and said unto them,.... Being not in the least intimidated by such a body of men: I will also ask of you one question; or "one word", or "one thing"; here answers to the Hebrew word which signifies both "word" and "thing": and answer me, and I will tell you by what authority I do these things; See Gill on Mat 21:24.