Jesus calling himself the Bread of Life and pointing out that nobody had seen God were references to Exodus. In that story, God fed the Israelites with manna, and the manifestations of God were always veiled. God never appeared in person. Now Jesus is present to fill both of those roles: seeing him is seeing God, and he himself will become the bread that feeds God's people. Not physical bread, or we couldn't live forever. What Jesus gives by fully inhaling him is abundant life, forever, starting now.