The argument between Jesus and the Jewish establishment continues, and now the figure of Abraham is dragged in. The Jews were intensely proud of being children of Abraham, as he had received a promise from God that a great nation would rise from his offspring, a promise which was sealed with a covenant.
Jesus has said, If anyone obeys my teaching he will not know what it is to die. In other words, he will gain eternal life. So the Jews challenge him. They say, “are you greater than our ancestor Abraham and greater than his teachings ? Are you greater than all prophets ? You, who are barely fifty years old !”
In reply, Jesus refers to the promises made to Abraham: and says, “your father Abraham rejoiced at the prospect of seeing my day come. Abraham rejoiced that he and his offspring would bear the messiah in generations to come, and this indeed was his blessing.” Jesus puts it with unmistakeable emphasis: “For before Abraham was born, I am.”
This expression “I am” is the formula of God’s revelation, first encountered in the book of Exodus, when God tells Moses his true name, in the episode of the burning bush. It appears again and again in John’s Gospel, as the evangelist portrays Jesus progressively revealing himself to the crowds, his disciples, even to his opponents.
How does he do this ? Jesus reveals himself as one of the same nature as God, sent by his Father to save humankind by inviting it into a personal relationship of trust in him. All Jesus’s miracles are signs that indicate this: The multiplication of the loaves is meant to reveal Jesus as the bread of life, our true nourishment. The festival of lights in the Temple reveals Jesus as the light of the world, without which anyone stumbles into sin. The raising of the dead Lazarus reveals Jesus, giving to his believer a power that stretches across life and death.