What is the meaning of Matthew 16:4?

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

A wicked and adulterous generation demands a sign, but none will be given it except the sign of Jonah.” Then He left them and went away.

Berean Standard Bible (BSB)

An evil and adulterous generation seeks after a sign, and there will be no sign given to it, except the sign of the prophet Jonah.” He left them, and departed.

World English Bible (WEB)

A wicked{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)} unto it{G846}, but{G1508} the sign{G4592} of the prophet{G4396} Jonas{G2495}. And{G2532} he left{G2641}{(G5631)} them{G846}, and departed{G565}{(G5627)}.

Strong's King James

(4) An evil and adulterous generation wishes for a sign and a sign won't be given it, except the sign of Jonah. He left them, going away.

The F.O.G*

[4] This faithless and morally adrift generation keeps demanding supernatural proof, but they've already ignored countless signs. The only sign they'll receive is what I'll share with the prophet Jonah—three days that will change everything." With that, Jesus left them standing there, His words hanging heavy in the air.

The F.O.G Paraphrase

‘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;’ and having left them he went away.

Young's Literal Translation