The account of the feeding of the 5000 as reported in John chapter 6 is really a tragic story; the same people Jesus had miraculously fed eventually rejected Him. Their expectations were for a political solution to their plight, and a king who can produce food instantaneously for thousands of people would have made a good candidate:
When the people saw the sign he had done, they said, “This is truly the Prophet, the one who is to come into the world.” Since Jesus knew that they were going to come and carry him off to make him king, he withdrew again to the mountain alone (vss. 14-15).
He gives them the slip until they catch up to Him in Capernaum:
And when they found him across the sea they said to him, “Rabbi, when did you get here?” Jesus answered them and said, “Amen, amen, I say to you, you are looking for me not because you saw signs but because you ate the loaves and were filled” (vss. 25-26).
Commenting on this passage, theologian Ronald Knox affirms that Jesus had come to provide only for their spiritual plight:
[O]ur lord is disturbed by the earthly-minded ambition on the part of his followers which would make a king of him. …Political activity is not the service to which the true kingdom is calling them.†
The temporal/worldly versus the spiritual/eternal is a theme that persists throughout the discourse:
Do not work for food that perishes but for the food that endures for eternal life, which the Son of Man will give you. For on him the Father, God, has set his seal” (vs. 27).
This begins the “Bread of Life” discourse, a prophetic description of the sacrament of the Eucharist. Jesus repeats four times to the crowd of followers that they would have to eat His flesh and drink His blood in order to have eternal life. When they realized that this was a reference to cannibalism, they deserted Him, and Jesus did nothing to prevent it because they had understood Him correctly, but faithlessly.
It is possible that this whole dialogue was specifically aimed at the twelve disciples, to whom He asks:
“What if you were to see the Son of Man ascending to where he was before?” (vs. 62).
This question, also prophetic since this is exactly what the disciples would experience, puts them in a corner. Let me paraphrase Jesus’ words,
“I just told you that to have eternal life you must consume my real body and blood. So how will you do that when I’m no longer here?”
“It is the spirit that gives life, while the flesh is of no avail. The words I have spoken to you are spirit and life” (vs. 63).
Jesus is reminding His disciples of the distinction between the spiritual and the earthly. They had seen Him change water into wine and feed thousands with a few loaves of bread, etc. That He would provide His body and blood in a spiritual manner should not have been impossible for them to believe.
The dialogue as a whole is a reminder that the mission of Christ and the Church is a spiritual one as opposed to an earthly one. The political issues of today: climate change, the alleviation of poverty, immigration etc., are the latter and are not the priorities of the “true kingdom”, and should not be the priorities of Church authorities today.
†A Commentary on the Gospels, New York: Sheen and Ward, 1952, p. 225.