About John 6.41 etc....
I've always found "John" pretty indigestible, because he depicts Jesus strutting about, striking poses, delivering pompous theological discourses... This is not at all the man we know and love from his incisive behavior and speech in the synoptic gospels--and the contrast severely annoyed me.
Whether or not Christians had invented The Trinity when this was written, a similar metaphor seems to be in the background here. It is not that analytically detailed metaphor which The Church eventually struggles to specify-- but a more flexible notion, confusing enough that I do see inspiration at work in it.
In the synoptics... Jesus occasionally speaks for God, not in the typical prophetic "Thus says the Lord" framing, but implicitly. "Whatever you've done to the least of my [siblings] you've done to Me," is the best example I know-- and utterly convincing.
Here, he becomes practically a full-time avatar, continually insisting that not only "The Father" is God, but so is The Son aka himself. God hasn't just "sent" him (as in the synoptics) but he's come down "from Heaven"; he is the bread that came down from there.
The allusion, of course, is to God feeding the Israelites on their walk out of Egyptian slavery. As in Exodus, they "murmur", they kvetch, and "John" disapproves, presuming that God disapproves likewise! "The Jews" aka John's contemporaries won't even eat this manna!-- and if they were listening to God, John's Jesus says, they'd be led right to him.
"And I will raise him up on the last day." Huh? The connection seems elusive...
But everyone in the true Israel-- those who keep wrestling with God-- "shall all be taught by God." And that teaching--at least in my life-- seemed inevitably to bring me to the question: Who was this man and what was God doing with him?
One message the Bible carries implicitly-- is that God wants to talk, while human beings-- including those writing the Bible itself-- "hear" God's communications through all the 'transference'/'counter-transference' distortions ever encountered between human patients & shrinks...
If one sees "the world" as the product of "God working within limitations"-- then human beings can be described as "God living within limitations." That mystical awareness that our very life is God... sets up a tension, between that and our experience of being very limited indeed.