An evil and [morally] unfaithful generation craves a [miraculous] sign; but no sign will be given to it, except the sign of [the prophet] Jonah.” Then He left them and went away. [Jon 3:4, 5]
Then the Lord said, “My Spirit shall not strive and remain with man forever, because he is indeed flesh [sinful, corrupt—given over to sensual appetites]; nevertheless his days shall yet be a hundred and twenty years.”
Even though they bring up their children, Yet I will bereave them until not one is left. Indeed, woe (judgment is coming) to them when I look away and withdraw [My blessing] from them!
Now the Lord had prepared (appointed, destined) a great fish to swallow Jonah. And Jonah was in the stomach of the fish three days and three nights. [Matt 12:40]
He groaned and sighed deeply in His spirit and said, “Why does this generation demand a sign? I assure you and most solemnly say to you, no sign will be given to this generation!”
For whoever is ashamed [here and now] of Me and My words in this adulterous and sinful generation, the Son of Man will also be ashamed of him when He comes in the glory of His Father with the holy angels.”
But since the Jews kept resisting and opposing him, and blaspheming [God], he shook out his robe and said to them, “Your blood (damnation) be on your own heads! I am innocent of it. From now on I will go to the Gentiles.” [Acts 13:46]