Matthew 16:1-8

Now the Pharisees and Sadducees came up, and testing Jesus [to get something to use against Him], they asked Him to show them a sign from heaven [which would support His divine authority]. But He replied to them, “When it is evening, you say, ‘It will be fair weather, for the sky is red.’ And in the morning, ‘It will be stormy today, for the sky is red and has a threatening look.’ You know how to interpret the appearance of the sky, but cannot interpret the signs of the times? 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] When the disciples reached the other side of the sea, they realized that they had forgotten to bring bread. Jesus said to them, “Watch out and be on your guard against the leaven of the Pharisees and Sadducees.” They began to discuss this among themselves, saying, “He said that because we did not bring bread.” But Jesus, aware of this, said, “You men of little faith, why are you discussing among yourselves that you have no bread?