30 For even as Jonah became a sign to the Ninevites, so will also the Son of Man be to this generation.
*Minor differences ignored. Grouped by changes, with first version listed as example.
As Jonah was a sign to the Ninevites. He declares that he will be a sign to them, as Jonah was to the inhabitants of Nineveh. But the word sign is not taken in its ordinary sense, as pointing out something, but as denoting what is widely removed from the ordinary course of nature. In this sense Jonah's mission was miraculous, when he was brought out of the belly of the fish, as if from the grave, to call the Ninevites to repentance. Three days and three nights This is in accordance with a well-known figure of speech. As the night is an appendage to the day, or rather, as the day consists of two parts, light and darkness, he expresses a day by a day and a night, and where there was half a day, he puts down a whole day.
For as Jonas was a sign to the Ninevites,.... As he was by lying three days and three nights in the whale's belly, and then cast on shore alive; which sign, or miracle was wrought to confirm his mission and message, and to engage the Ninevites to give credit to him, and repent, or they might assure themselves they would be utterly destroyed;
so shall also the son of man be to this generation; by lying three days and three nights in the heart of the earth, and then rising again from the dead the third day; and which should be done to confirm the truth of his Messiahship, and to declare him to be the Son of God with power, and to engage persons to believe in him; and to assure that wicked generation, that in case they remained, after such a sign, impenitent and unbelieving, wrath would come upon them to the uttermost; see Matthew 12:40.
*More commentary available at chapter level.