"Having eyes, see ye not? and having ears, hear ye not? and do ye not remember?" Mark 8:18
At this point, the disciples had witnessed the feeding of thousands of people with few loaves of bread, and now, in the boat with Jesus, they had forgotten to bring along with them bread. Speaking to them, Jesus charged them to be mindful of the leaven of the Pharisees, which was false doctrine, and the leaven of Herod, which was false messianic claim. Of these two 'leavens', we do also do well to be mindful of today.
But the disciples did not understand what He was saying to them, and thought that He was speaking to them regarding their failure to bring bread. The response of Jesus to their thoughts is also a lesson for us. Jesus said to them, do you not remember? He definitely expected them to remember what happened, when, with five loaves and two fishes, five thousand men were fed, excluding women and children; when, four thousand people were fed with seven loaves and a few fishes. But they did not remember. God expects us to also remember the things He had done for us in the past, and by them learn that He will yet do more for when next we are challenged.
When David came against Goliath, he remembered the past dealings of God in his life, and in the assurance that it brought, he faced the giant and slew him. So, let us remember.
Toni