In verses 32-33, Jesus makes His first obvious move to reveal that we are to eat of Him. Put into modern English, Jesus says, "Moses was merely God's agent who gave directions to the people on how to collect the manna. My Father in heaven is the real Giver. Even if you consider Moses to be the giver, he did not give the real heavenly bread. The Father is right now giving the real bread from heaven. I am that real bread of life." Jesus is the One we are to ingest and assimilate into our lives.
Jesus does not mean that manna had no physical value but that it was not a means of sustaining spiritual life. Nothing physical can do this. Physical things may please us, even exhilarate us, but they can give no lasting sense of well-being.
Clearly, Jesus intends that we understand all of this spiritually, including the word "life." Life, as Jesus means it, is the way God has lived from eternity. In and through Christ, we can share in it if we will "eat" Him, the "bread" of that life. In verse 34, the people reply, "Lord, give us this bread always," showing that they now understand enough to desire the bread but not its spiritual application. In verse 35, then, He responds by identifying Himself undeniably as the bread of life, adding, "He who comes to Me shall never hunger, and he who believes in Me shall never thirst." He declares that He is the only permanent satisfaction for the human desire for life and that attaining this satisfaction hinges on belief, a commitment to Him based on trust.
When we connect this final thought with verses 26-29, it becomes clear that faith, which enables the establishment of an intimate fellowship and union with Him, makes it possible to ingest and assimilate Him spiritually. By assimilating Him spiritually, as we assimilate bread physically, man can attain everlasting life.
The faith or belief Christ means is a deep-seated commitment exercised by humbly coming to Him as one who knows that he has nothing and needs everything to have the kind of life God lives. Much as a plant turns towards the sun, one with a commitment like this will turn to Him for everything, knowing that without Him we can do nothing (John 15:5).