Matthew Henry Commentary Mark 11:27-33

"And they come again to Jerusalem: and as he was walking in the temple, there come to him the chief priests, and the scribes, and the elders; and they said unto him, By what authority doest thou these things? or who gave thee this authority to do these things? And Jesus said unto them, I will ask of you one question, and answer me, and I will tell you by what authority I do these things. The baptism of John, was it from heaven, or from men? answer me. And they reasoned with themselves, saying, If we shall say, From heaven; He will say, Why then did ye not believe him? But should we say, From men--they feared the people: for all verily held John to be a prophet. And they answered Jesus and say, We know not. And Jesus saith unto them, Neither tell I you by what authority I do these things." — Mark 11:27-33 (ASV)

Our Savior shows how closely related His doctrine and baptism were to those of John; they had the same design and tendency, to bring in the gospel kingdom.

These elders did not deserve to be taught; for it was plain that they contended not for truth, but for victory. Nor did He need to tell them. For the works He did told them plainly that He had authority from God, since no man could do the miracles which He did, unless God was with Him.