Q --

I don't know. It is true that there was already much trade between the Jews and the Greeks at that time, so it may have just been common knowledge.

Or, it could be that the person who wrote that story down was translating what Jesus said for a Greek audience, and figured that using "Alpha and Omega" would be be clearer than using "Alef and Tav,"
and then trying to explain what that meant.

...Did you try Googling "QWERTY" instead of "querty?"