An evil and adulterous generation seeks after a sign, and there will be no sign given to it, except the sign of the prophet Jonah." He left them, and departed. The disciples came to the other side and had forgotten to take bread. Jesus said to them, "Take heed and beware of the yeast of the Pharisees and Sadducees." read more.
They reasoned among themselves, saying, "We brought no bread." Jesus, perceiving it, said, "Why do you reason among yourselves, you of little faith, 'because you have brought no bread?' Don't you yet perceive, neither remember the five loaves for the five thousand, and how many baskets you took up? Nor the seven loaves for the four thousand, and how many baskets you took up? How is it that you don't perceive that I didn't speak to you concerning bread? But beware of the yeast of the Pharisees and Sadducees." Then they understood that he didn't tell them to beware of the yeast of bread, but of the teaching of the Pharisees and Sadducees.

He left them, and again entering into the boat, departed to the other side. They forgot to take bread; and they didn't have more than one loaf in the boat with them. He warned them, saying, "Take heed: beware of the yeast of the Pharisees and the yeast of Herod." read more.
They reasoned with one another, saying, "It's because we have no bread." Jesus, perceiving it, said to them, "Why do you reason that it's because you have no bread? Don't you perceive yet, neither understand? Is your heart still hardened? Having eyes, don't you see? Having ears, don't you hear? Don't you remember? When I broke the five loaves among the five thousand, how many baskets full of broken pieces did you take up?" They told him, "Twelve." "When the seven loaves fed the four thousand, how many baskets full of broken pieces did you take up?" They told him, "Seven." He asked them, "Don't you understand, yet?"