More on Arabic glosses from p.118 Parker:
"Another note provides a date before which the note must have been written. Across the bottom of Q90-F4r, probably annotating 8.1 onwards, is a long comment explaining the prophecy of the seventh seal ([....] indicates unreadable text):
And at the beginning of the seventh thousand a persecution [of Christians] will take place. They say that [other] martyrs, who were martyred on the Messiah's lance [...] Then peace and calmness will come and the number of holy men increase. Their [...] will be eleveated and will compel them to appear in front of the Lord. And as a consequence will appear then a star of the Arabs, which looks like hellebore, will appear [...] This star is called afsintis, which is absinth, It will fall into the water and many [...]
The seventh thousand is probably a reference to the date in the Byzantine calendar, which would be 1491 AD. The word afsintis is a colloquial form, which may be associated with the Near Eastern drug trade. The spelling suggests that the writer was a Syrian.
Predictions that the world would end seven thousand year after its creation (1492 in the common reckoning) were made in the years after the fall of Constantinople in 1453. The first Patriarch under Ottoman rule, Gennadios II Scholariosm foretold that it would come on 1st Sept. This explains the glossator's interest in the Apocalypse, and gives an approximate date (after 1453 and before 1492) for the gloss.
The Arabic glosses are, unfortunately, the only evidence for the six hundred years between the 12th century glosses and the middle of the eighteenth century. It is highly probable that the Codex was in St. Catherine's Monastery throughout that period. There is certainly no evidence to the contrary, and the presence of native Arabic speakers there is perfectly natural.
From the ninth century, the change in Greek script from majuscule to minuscule meant that fewer and fewer people were able to read the older scripts, until at last manuscriptys like the Codex became useless. It was common enough for the parchment to be scaped down and reused (as was the case with the Codex Ephraemi Rescriptus). From this point on, Codex Sinaticus is unlikely to have been used regularly."