Matthew 12:38-42
38 Then some of the scribes and Pharisees said to him, “Teacher, we wish to see a sign from you.”
39 But he answered them, “An evil and adulterous generation asks for a sign, but no sign will be given to it except the sign of the prophet Jonah.
40 For just as Jonah was three days and three nights in the belly of the sea monster, so for three days and three nights the Son of Man will be in the heart of the earth.
41 The people of Nineveh will rise up at the judgment with this generation and condemn it, because they repented at the proclamation of Jonah, and see, something greater than Jonah is here!
42 The queen of the South will rise up at the judgment with this generation and condemn it, because she came from the ends of the earth to listen to the wisdom of Solomon, and see, something greater than Solomon is here!
“40 For just as Jonah was three days and three nights in the belly of the sea monster, so for three days and three nights the Son of Man will be in the heart of the earth.”
There is no reason for folks to dig up modern examples of nature kinda/sorta doing whatever they think God did with Jonah.
Jonah was perhaps NOT ‘alive’, in the physical sense, during those 3 days. Which would make Christ’s analogy more accurate.
Piece of cake for God/Jesus. Lazarus was 4 days dead.