A. K. Brook『The Jews of Khazaria』 pp.317-318
- circa 830s
- First Rus Kaganate is established.
- Saint Cyril visits Cherson and learns Hebrew.
- Saint Cyril debates in the Khazar court against Rabbi Yitzhak ha-Sangari and a Muslim mullah.
- Most of the eastern Slavs become united.
『The Jews of Khazaria』 pp.121-124の、「Saint Cyril's Khazarian Mission」
『The Jews of Khazaria』 pp.81-82
For instance, the evangelist Saint Cyril gained extensive knowledge of Hebrew during his stay in the city of Cherson in 860-861 (See Chapter 6). Using his newly acquired knowledge, Cyril incorporated elements of Hebrew letters into the Glagolithic character set he developed; for instanse, the letter Ш (representing the sound sh) was derived from the Hebrew letter shin.