And they reasoned among themselves, saying, It is because we have taken no bread.
Read Chapter 16
Wherefore also He works another miracle, and then and not till then He reproves; I mean, He brings forward what they were reasoning in their hearts. But what were their reasonings? Because, so it is said, we have taken no bread. For as yet they were full of trepidation about the purifications of the Jews, and the observances of meats.
Note how intense is his displeasure. Nowhere else does he appear to have rebuked them so much. How does he do this? He is challenging their prejudices about food laws. Already he had said, “Are you still without understanding?” Now in this place, with a strong rebuke he says, “O men of little faith.” The Gospel of Matthew, Homily