Matthew 21:24-27

24And Jesus answering said to them, I also will ask you one thing, which if ye tell me, I also will tell you by what authority I do these things:

25The baptism of John, whence was it? of heaven or of men? And they reasoned among themselves, saying, If we should say, Of heaven, he will say to us, Why then have ye not believed him?

26but if we should say, Of men, we fear the crowd, for all hold John for a prophet.

27And answering Jesus they said, We do not know. He also said to them, Neither do I tell you by what authority I do these things.