I havn't continued the above discussion, as it is likely to get bogged down in logical semantics. It's difficult for Christians to accept that Jesus who had (in both orthodoxy and JWism) a pre-human existence could ever be affected by an alien culture.
Bur, since all we know about 'Jesus' was written by someone else those writers, at leasts, could have been culturally influenced by Greek ideas.
Let me give a small example. In Luke 24 it is claimed that the resurrected Jesus appeared in a (different) human form and the disciples only recognised him after he blessed and broke some bread (in a manner that he-Jesus- had always done) verses 30 to 31 tells that story.
Quote: "30 When he was at the table with them, he took bread, gave thanks, broke it and began to give it to them. 31 Then their eyes were opened and they recognized him, and he disappeared from their sight. 32 They asked each other, “Were not our hearts burning within us while he talked with us on the road and opened the Scriptures to us?”" Luke 24: 30-32 NIV
Unless we knew something about Greek culture the time, we'd likely miss the point. Robin Lane Fox, in his book 'Pagans and Christians in the Mediterranean World.' and Ch. 4 titled 'Seeing the gods' explains that in Greek culture it was believed that the gods would often appear to humans in human form but not recogniswable as a god. The human visited by such a divinity would only recognise the god through some small sign by which the god would reveal himself,
We can therefore imagine that the author of Luke's gospel knew 'Greek' culture and could his 'Jesus' story using memes that were known if Greek (not Jewish) culture.
Another of the text books used in a Study Unit in which I enrolled at Macquarie U was, 'Introducing the New Testament: Its Literature and Theology,' ( Achtemeier, Green and Thompson - Eerdmans 2001). In the first chapter, the authors discuss the influence of Hellenism on Jewish society and expresses the claim that both Jesus and his disciples would have been able to communicate in Greek, even if they spoke Aramaic.
We will not (short of the discovery of some unknown document that describes Jesus more clearly) ever know whether Jesus could speak Greek, or that he addresses the groups that heard him in Greek, But it must be clear that if Jesus was just a human (and had no pre-existence) then he also grew up in a world in which the culture of the Greeks prevailed.