Apparently the 300 refers to the number of Philistines Samson killed when he pulled those pillars down, and Themistocles is the name of the arch enemies of the Bionicles.What Greek literature(besides the bible, obviously) have you read, then?
Wiki has an easily accessible article on the subject.
Anyway. Just like several religions have ex nihilo creation myths, so do several religions have prophecies as a central part of their religious practice and beliefs, like the Romans, the Greeks, heck even New Age is big on prophecy. Their claims are as "accurate" as those of the bible.
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