The book of Ben Sira, thought to have been written around 200 BCE, consists mostly of proverbs and aphorisms. While it appears (under the title Ecclesiasticus) in Catholic editions of the Bible, it never entered the Jewish canon and is largely unknown to Jews today. Yet, notes Michael Satlow, Jews continued to read and study it long after it was definitely excluded from Scripture.
Unlike other originally Jewish books now found in the [Christian] Apocrypha, . . . Ben Sira did not exactly fade away. The book continued to circulate and to be read among Palestinian Jews, even though some 2nd- and 3rd-century rabbis explicitly put it in the category of non-holy, even heretical, books. Yet in practice, Palestinian rabbinic literature shows no discomfort with reading and citing the book.
The Palestinian Talmud mentions the book once, in a story in which Shimon ben Shetaḥ quotes from it in order to justify his actions to King Yanai. While the Palestinian Talmud never cites verses from Ben Sira using the traditional terms used to introduce biblical prooftexts, in several places it introduces verses from Ben Sira with a formula like, “Ben Sira said,” as if he himself was a [talmudic] sage like any other. . . .
Indeed, the fact that Ben Sira continued to play an important role in the lives of Palestinian Jews can be attested by the very survival of the Hebrew text in the Cairo Geniza. Portions of five manuscripts were found, all carefully written. We do not know how this community (which had close ties to the Jewish community in the land of Israel) used these books; since they were not written on parchment, it likely did not use them liturgically.
Read more on theTorah.com: http://thetorah.com/the-wisdom-of-ben-sira-how-jewish/