In the Old Testament, in the Book of Exodus, when Israel was wandering in the desert, God fed them manna from heaven: “Moses said to them, ‘It is the bread the Lord has given you to eat” (Exodus 16:14-15), and water from a rock: The Lord answered Moses, ‘Walk on ahead of the people. Take with you some of the elders of Israel and take in your hand the staff with which you struck the Nile, and go. I will stand there before you by the rock at Horeb. Strike the rock, and water will come out of it for the people to drink”(Exodus 17:6).
These were symbols of the True Bread from heaven, and the Water of Life. In John 6:30-31 the people asked Jesus “What miraculous sign then will you give that we may see it and believe you? What will you do? Our fathers ate the manna in the desert; as it is written: He gave them bread from heaven to eat”.
Jesus tells them that this was only a figure or illustration of the true bread from heaven. “Jesus said to them, I tell you the truth, it is not Moses who has given you the bread from heaven, but it is my Father who gives you the true bread from heaven. For the bread of God is he who comes down from heaven and gives his life to the world”.
But they didn’t understand the spiritual significance of what He was saying and thought he is talking about physical bread: “Sir,” they said, “from now on give us this bread”. Then Jesus makes it very clear to them: “I am the bread of life, he who comes to me will never go hungry, and he who believers in me will never be thirsty” (verses 32-35).
In verses 47-51 Jesus continues: “I tell you the truth, he who believes in me has everlasting life. I am the bread of life. Your forefathers ate the manna in the desert, yet they died. But here is the bread that comes down from heaven, which a man may eat and not die. I am the living bread that came down from heaven. If any one eats of this bread, he will live forever. This bread is my flesh, which I will give for the life of the world”.
I Corinthians 10: 3-4: gives added details of this truth, the spiritual meaning of the manna and the water that came out of the rock: “They all ate the same spiritual food and drank the same spiritual drink; for they drank from the spiritual rock that accompanied them, and that rock was Christ (a symbol of Christ) .”