No. It's dialect of extincted Slavs living arroun  Thesaloniki in IX century. It was enriched by influences from Byzantine Greek, mostly in way of making new words, but it almost eclusively used Slavic roots. :) Also it had some local influences, but it is not aritificiaily created, it's codified dialect improved for liturgical and literal use. Church Slavonic is newer version created amogn Eastern Slavs, it has more Eastern Slavic influence, and it is today in use by Slavic Orthodox and Byzantine Chatolic Churches.

I don't think those Slavs are extinct. This guy is an example that they are not. This had been posted many times but obviously nobody paid attention.

Razgovor so eden Makedonec