What is the meaning of Matthew 12:39?

* The two F.O.G. Bibles & Commentary below are currently a work in progress.

Jesus replied, “A wicked and adulterous generation demands a sign, but none will be given it except the sign of the prophet Jonah.

Berean Standard Bible (BSB)

But he answered them, “An evil and adulterous generation seeks after a sign, but no sign will be given it but the sign of Jonah the prophet.

World English Bible (WEB)

But{G1161} he answered{G611}{(G5679)} and said{G2036}{(G5627)} unto them{G846}, An evil{G4190} and{G2532} adulterous{G3428} generation{G1074} seeketh after{G1934}{(G5719)} a sign{G4592}; and{G2532} there shall no{G3756} sign{G4592} be given{G1325}{(G5701)} to it{G846}, but{G1508} the sign{G4592} of the prophet{G4396} Jonas{G2495}:

Strong's King James

(39) But He answered, saying to them, "An evil and adulterous generation desires a sign and no sign will be given it except the prophet Jonah's sign.

The F.O.G*

[39] Jesus responded firmly: "An evil and faithless generation craves miraculous signs, but none will be given except the sign of the prophet Jonah.

The F.O.G Paraphrase

And he answering said to them, ‘A generation, evil and adulterous, doth seek a sign, and a sign shall not be given to it, except the sign of Jonah the prophet;

Young's Literal Translation