'''Sozomenus''' described the religion of the Saracens in the 5th century saying that they descended from Ishmael and their religion if any different from Judaism was only because of the passage of time and their interaction with non-Jews.
From this we understand that the Ishmaelites should have belonged the same religion as Judah ben Tabbai. This causes us to wonder why Sebeos said that the Jews from Edessa could not convince the Ishmaelites of Tachkastan to unite with them in religion.!?
