Luke 20:5

5 They argued about this, saying, "If we answer, 'John's baptism was from God,' Jesus will say, 'Then why did you not believe him?'

Luke 20:5 Meaning and Commentary

Luke 20:5

And they reasoned with themselves
Or "they thought with themselves", as the Syriac version; or "within themselves", as the Vulgate Latin, though they did not express it; or "one with another", as the Arabic version; they took counsel together, and debated the matter among themselves, and reasoned after this manner:

saying, if we shall say from heaven;
which was what, in their own consciences, they believed to be true,

he will say, why then believed ye him not?
in what he said concerning the Messiah; which if they had, as they should, there would have been no reason for such a question they had put; (See Gill on Matthew 21:25).

Luke 20:5 In-Context

3 Jesus answered, "I will also ask you a question. Tell me:

4 When John baptized people, was that authority from God or just from other people?"

5 They argued about this, saying, "If we answer, 'John's baptism was from God,' Jesus will say, 'Then why did you not believe him?'

6 But if we say, 'It was from other people,' all the people will stone us to death, because they believe John was a prophet."

7 So they answered that they didn't know where it came from.