37 Here δέ (de) has been translated as “So” to indicate that the clause is a result of the deliberations of the leaders.
38 Grk “answering Jesus, they said.” This construction is somewhat awkward in English and has been simplified in the translation.
39 Very few questions could have so completely revealed the wicked intentions of the religious leaders. Jesus’ question revealed the motivation of the religious leaders and exposed them for what they really were—hypocrites. They indicted themselves when they cited only two options and chose neither of them (“We do not know”). The point of Matt 21:23–27 is that no matter what Jesus said in response to their question, they were not going to believe it and would in the end use it against him.
40 Neither will I tell you. Though Jesus gave no answer, the analogy he used to their own question makes his view clear. His authority came from heaven.
41 On this phrase, see ποῖος 2.a.γ. This is exactly the same phrase as in v. 23.

In other versions

So they answered Jesus, “We do not know.” And he said to them, “Neither will I tell you by what authority I do these things.

So they answered Jesus, “We don’t know.”

Then he said, “Neither will I tell you by what authority I am doing these things.

So they answered Jesus, “We don’t know.”

And he said to them, “Neither will I tell you by what authority I do these things.

So they finally replied, “We don’t know.”

And Jesus responded, “Then I won’t tell you by what authority I do these things.

And they answered and said to Jesus, “We do not know.” And he said to them, “Neither will I tell you by what authority I am doing these things.

And they answered Jesus, and said, We cannot tell. And he said unto them, Neither tell I you by what authority I do these things.

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