Those Who Will Not Look and Those Who Cannot See
The Pharisees will not look and the disciples cannot see. The Pharisees in this new place want a sign - perhaps legitimately - to authenticate the authority of Jesus. However, Jesus does not give them a sign because they came with hard hearts. Jesus uses the picture of the bread to warn the disciples against the Pharisees but all they can think of is their immediate predicament. Jesus had just fed four thousand! Do they really think they won't have enough to eat? He gives us what we need and we must look to Him in our anxieties.