[Verv]

The Novgorod Codex is a great topic and the wikipedia article is definitely worth your read. I'd love to know more about it for a variety of reasons. But from the wikipedia there is the following line that I would like to have clarified:

Finally, another text that Zaliznyak calls “Spiritual Instruction from the Father and the Mother to the Son” contains the following note “Въ лѣто ҂ѕ҃ф҃з҃ азъ мънихъ исаакии поставленъ попомъ въ соужъдали въ цръкъве свѧтаго александра арменина…” (“In 6507 [i.e. 999] I, monk Isaakiy, was posted as a priest in Suzdal, at the church of St. Alexander the Armenian…”). The year 6507/999 reappears several times on the margins, and is the only numerical sequence identified in the text.

http://en.wikipedia.org/wiki/Novgorod_Codex

This number system isn't clarified. What people said that the year 999 was 6507, and how was this concluded?

For a second I wondered if there was some old Roman calendar that they were still somehow using then, but it appears that Romans counted the year zero from the foundation of Rome, often attributed to the 8th century BC, and that isn't the case.

Does anyone know what sort of calendar, at that time, would be dating the year as 6507? Where did they conclude that this corresponds to the year 999?

Very interesting topic and I invite all other discussion on the Novgorod Codex.

[Lexington]

This number system isn't clarified. What people said that the year 999 was 6507, and how was this concluded?

Byzantine calendar

Its year one, the supposed date of creation, was September 1, 5509 BC to August 31, 5508 BC.

Early/medieval Christians seem to have dated the world about a thousand years older than the Jews ended up doing.

[Verv]

Oh wow, thank you; what a fabulous find for me.

I appreciate your efforts & bow to your knowledge on the topic.