Mark 8:13-15

¹³And he left them, and went up again into a boat, and went over the sea.

¹⁴And they forgot to take bread, and they had not with them but one loaf in the boat.

¹⁵And he commanded to them, and said, See ye, and beware of the sourdough of the Pharisees, and of the sourdough of Herod.