Matthew 12:38-40

³⁸Then some of the scribes and Pharisees said to Him, “Teacher, we want to see a sign from You.” ³⁹But He answered and said to them, “An evil and adulterous generation craves for a sign; and yet no sign will be given to it but the sign of Jonah the prophet; ⁴⁰for just as Jonah was three days and three nights in the belly of the sea monster, so will the Son of Man be three days and three nights in the heart of the earth.