Matthew 16:1-4

One day some of the Pharisees and those of the Jewish sect known as the Sadducees approached Jesus, insisting that he prove to them that he was the Messiah. “Show us a supernatural sign from heaven,” they demanded. Jesus answered, “You can read the signs of the weather, for you say, ‘Red sky at night, sailors delight.’ And, ‘Red sky in the morning, sailors take warning.’ You’re so adept at forecasting the weather by looking at the sky, but you’re absolutely clueless in reading the obvious signs of the times. A wicked and wayward generation always asks for signs, but the only sign I provide for you will be the sign of Jonah the prophet.” Then he turned away and left them.