From a commentary on St. John's Gospel by St. Theophylact
Our Lord refers to himself as the true bread not because the manna was something illusory, but because it was only a type and a shadow, and not the reality it signified.
|5th c. mosaic,Church of the Multiplication of the Loaves and Fish, Tabgha, Israel.|
This bread, being the Son of the living Father, is life by its very nature, and accordingly gives life to all. Just as earthly bread sustains the fragile substance of the flesh and prevents it from falling into decay, so Christ quickens the soul through the power of the Spirit, and also preserves even the body for immortality. Through Christ resurrection from the dead and bodily immortality have been gratuitously bestowed upon the human race.
Jesus said to the people: “I am the bread of life. Whoever comes to me shall never hunger, and whoever believes in me shall never thirst.” He did not say “the bread of bodily nourishment” but “the bread of life”. For when everything had been reduced to a condition of spiritual death, the Lord gave us life through himself, who is bread because, as we believe, the leaven in the dough of our humanity was baked through and through by the fire of his divinity. He is the bread not of this ordinary life, but of a very different kind of life which death will never cut short.
Whoever believes in this bread will never hunger, will never be famished for want of hearing the word of God; nor will such a person be parched by spiritual thirst few lack of the waters of baptism and the consecration imparted by the Spirit. The unbaptized, deprived of the refreshment afforded by the sacred water, suffer thirst and great aridity. The baptized, on the other hand, being possessed of the Spirit, enjoy its continual consolation.