Did Pericles say something on another thread that made him persona non grata at some point? I really cannot see anything wrong with his premise from a historical or religious standpoint.
At the time, Hellenistic culture was all the parts of the world influenced by the Greeks. It was probably the major culture of the Mediterranean. The Romans were "Hellenistic". Before them the region had the various successor dynasties (Seleucids, Ptolemies) and various cities were highly Hellenized - Cyrene, Antioch, etc. In the Bible it seems that the words "Greek" and "Gentile" are almost used interchangeably.
And whether Christianity was Jewish or Greek was debated in the early church and I would argue that Greek (if we use the term very loosely) won out. Hellenism wasn't just Greek, it was any culture influenced by the Greeks (As Pericles rightly pointed out). Early on it was decided that Christians did not have to be simultaneously Jewish. They did not have to have Jewish blood, they did not have to be circumcised, they did not have to restrict their diet in the same ways.
Of course Jewish culture influenced Christianity, I mean, look at the men who spread it after the Ascension! But I would wager that the Hellenistic cultures were all influenced by the nations they took root in. (E.G. - Ptolemaic brother-sister-godking-love). So obviously Christianity would have many Jewish influences, but I don't think this would make it any less Hellenistic.
That said, I am only talking about this as an historical phenomenon. Christianity has taken on many other cultures over the years. There are noticeable Germanic/Celtic/Egyptian-Coptic/Slavic variations of Christianity in the world today, and probably more. As Christianity grows in Africa and East Asia separate from European Colonialism in the next couple centuries I expect to see cultural elements from those regions to also start making their mark. In some places this will not affect the truth in any way, and in others it may lead to heresy. This is nothing new.