Where did the Jesus myth come from?

[Tea Earl Grey Hot]

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Show me the controversy. I see Peter willingly going to Cornelius - a devout and God-fearing man who gave generously to those in need and prayed to God regularly. What would bother Peter about THAT?

Peter only went to Cornelius after the vision. Peter didn't know about him before the vision.

Here's Peter's vision:

[10] And he became hungry and desired something to eat; but while they were preparing it, he fell into a trance
[11] and saw the heaven opened, and something descending, like a great sheet, let down by four corners upon the earth.
[12] In it were all kinds of animals and reptiles and birds of the air.
[13] And there came a voice to him, "Rise, Peter; kill and eat."
[14] But Peter said, "No, Lord; for I have never eaten anything that is common or unclean."
[15] And the voice came to him again a second time, "What God has cleansed, you must not call common."
[16] This happened three times, and the thing was taken up at once to heaven.
[17]
Now while Peter was inwardly perplexed as to what the vision which he had seen might mean, behold, the men that were sent by Cornelius, having made inquiry for Simon's house, stood before the gate

The animals, reptiles, and birds are metaphors for the Gentiles. They were unclean like the Gentiles were thought to be. But the vision is now telling Peter that the Gentiles have been "cleansed."

...How can Peter have been initially reluctant?

Where in Acts 10 is Peter reluctant?
Show me the verse.

But Peter said, "No, Lord; for I have never eaten anything that is common or unclean."

It is said that Peter refused three times to eat the unclean animals.

Also note the following verse:

But Peter lifted him up, saying, "Stand up; I too am a man."
[27] And as he talked with him, he went in and found many persons gathered;
[28] and he said to them, "You yourselves know how unlawful it is for a Jew to associate with or to visit any one of another nation; but God has shown me that I should not call any man common or unclean. (emphasis mine)

It's clear from the last verse in the above that Peter would not have done this if it wasn't for what he learned in the vision!
Another interesting part from chapter 10:

[45] And the believers from among the circumcised who came with Peter were amazed, because the gift of the Holy Spirit had been poured out even on the Gentiles.
[46] For they heard them speaking in tongues and extolling God. Then Peter declared,
[47] "Can any one forbid water for baptizing these people who have received the Holy Spirit just as we have?"

...How can his colleagues in Jerusalem have called him on the carpet, questioning his orthodoxy?

Does it say ''questioning his orthodoxy'' in Acts 11?
No. They were criticising his apparent lack of judgement in spending valuable time with, what turned out to be, a valuable group of people in the House of Cornelius. Peter didnt need to justify spending time with lepers, prostitutes, tax collectors, etc. any more than Jesus did.
What he did need to explain was the use of his short remaining time on earth. (ie. look at my avatar.)

Ahem...

So when Peter went up to Jerusalem, the circumcision party criticized him,
[3] saying, "Why did you go to uncircumcised men and eat with them?"

Uncircumcised men i.e. gentiles. I see no support for your idea that they were trying to be efficient. And now you're again begging the question: assuming Jesus did those things to prove he did those things. It's a form of circular reasoning and you're making me dizzy.

...If the parting words of the Risen Christ were a command to preach to Gentiles, whence the dispute?

Exactly!

There was no dispute about what Jesus commanded. (And continues to command.)
There was dispute about how best to go about doing that. (And continues to be.)

You have presented no evidence for that assertion. I having to wonder if maybe you're reading some paraphrased dumbed down Bible to think that's in the text. The verses I quoted I think show very plainly that they thought the gentiles were still unclean and unredeemable.

...Notice, too, that Peter is not simply stubborn: he is readily convinced by the vision of the animals and the sail-cloth (Acts 10:9-16) that he ought to heed Cornelius's invitation. But why did it take even this, if Jesus had not long before made it clear that the chief business of the apostles was to convert the heathen nations?

This is like saying that Jesus is prevented from repeating the same message because if He does then it must mean He never really said it the first time. Thats not logical. Again, Peter's vision persuades him to visit Cornelius at the expense of what he may have otherwise been inclined to do closer to home.

It's perfectly logical if the message Jesus repeats is seemingly forgotten by his followers including his disciples. Peter and his gang act like this is some new teaching that he got from the vision. And again, no evidence presented for this weird gospel efficiency theory you came up with.

...Clearly, then, the Great Commission sayings were coined only once the great Gentile Mission debate began, as an attempt by the liberal pro-mission faction to win their point...

No. Whats clear is that someone has a wacky theory that Jesus;

Are you talking about yourself?

* Never in His entire ministry EVER did or said anything which was controversial to Jewish kosher and ritual cleanliness laws.

* Neglected to share His concerns about misguided legalistic Judaism.

* Never intended All Nations to hear the Good News

* And that only late in the piece after He had been Resurrected, did He realise that the Gospel of salvation (which comes from the Jews) might need to be shared OUTSIDE OF JERUSALEM.

I'm not sure what you're trying to say here.