“Now the disciples had forgotten to take bread, and they did not have more than one loaf with them in the boat. Then He charged them, saying, “Take heed, beware of the leaven of the Pharisees and the leaven of Herod.”” (Mk. 8:14-15)
Jesus’ exhortation here implies that His disciples are bread. They are a lump of dough that must beware of particular kinds of leaven. Beware of the leaven of the Pharisees and Herod; the yeast they need is the yeast of Jesus. They need to be growing up into the one loaf, which is His body. One of the most common ways of leavening bread both in the ancient world and even still sometimes today is the practice of saving some of the dough from a previous batch of bread. That small piece of dough ferments and becomes the leaven for the next day’s bread. And so day after day, portions of bread are kept back to ferment and then mixed into the following day’s bread. And so John records Jesus right after the feeding of the five thousand saying, “Most assuredly, I say to you, Moses did not give you the bread from heaven, but My Father gives you the true bread from heaven. For the bread of God is He who comes down from heaven and gives life to the world… I am the bread of life. He who comes to Me shall never hunger, and he who believes in me shall never thirst… I am the living bread which came down from heaven. If anyone eats of this bread, he will live forever; and the bread that I shall give is my flesh, which I shall give for the life of the world.” And so I imagine Mark probably had a bit of a smirk on his face when I wrote this: “they only had one loaf with them in the boat.” There was only one loaf of bread in the boat; it was the bread of life come down from heaven for the life of the world. And you are this loaf, and each week you come here to be remade and renewed, and Jesus leavens you with His flesh so that you are flesh of his flesh and bone of his bone, for the life of the world.