In their frequent crossings of the lake, a boat serves as a classroom for Jesus’ disciples. However, they seem to keep missing the point he wants to teach them. In chapter 4 (vs 35–41), they are so terrified of the storm that they fail to grasp Jesus’ power until he has calmed the water. They lack faith. In chapter 6 (vs 45–52), they are filled with fear as Jesus walks to them on the water because ‘they had not understood about the loaves; their hearts were hardened’ (6:52). Now Jesus takes them back to the two miraculous feedings and they still don’t get it. Their hearts are hardened; they don’t remember (v 18). 

Jesus wants to warn them against the insidious unbelief of the Pharisees and the followers of Herod. These are people who see what Jesus does, but fail to join the dots to see who he is. The disciples are running the same risk. They fail to see the maths of the kingdom: the less Jesus has to work with, the more he produces! He himself is the bread we all need (see John 6:35). 

Fill thou my life, O Lord my God, / in every part with praise, / that my whole being may proclaim / thy being and thy ways.’¹

Jesus had already explained vividly that what defiles us comes from within. His original allegory was prompted by the Pharisees’ external piety, but now he targets their wrong attitude of heart and mind. The powerful spiritual symbol of bread sailed with Jesus and the disciples on the boat and now Jesus expands it. The little bit of yeast in the bread dough determines its final form. The parable of the two dogs fighting within us has been used by many preachers and writers, including Billy Graham and George Bernard Shaw. To the question, ‘Which dog wins?’, there is always the same response, ‘The one we feed’. One dog symbolises negative and ungodly qualities, including envy, greed, anger, selfishness and arrogance. The other dog’s qualities are positive and godly, including love, joy, kindness, humility and self-control. We choose the attitudes we nourish within us and they determine what we become.

The disciples did not catch on. Their apparent dullness is a significant, even perhaps purposeful, theme in the Gospels, as if there were a pact between the writers and the apostles never to glamourise themselves. They had indeed failed, constantly, to understand Jesus and his mission. They had argued about power and status. Peter would deny Jesus. Judas would betray him. Later, however, as the Gospel writers were recording their stories, they had at last understood it all. They had experienced the resurrection. Everything had come together in their hearts and minds, but they were the leaders of a church struggling in a hostile world. They did not want to be seen as heroes or celebrities. They were ordinary people whom Jesus called out of their ordinariness. When they met their risen Lord, they understood why. That was the yeast that now shaped them, the yeast that would rise to eternal life. 

Jesus, Lord of the path to eternity, nourish us when we are faint, lift us up when we fall and, when we lose the way, show us yourself.

¹ Horatius Bonar, 1808–89