Wisdom of Sirach (a.k.a. Ecclesiasticus)
The Book of the All-Virtuous Wisdom of Yeshua ben Sira, commonly called the Wisdom of Sirach or simply Sirach, and also known as the Book of Ecclesiasticus (abbreviated Ecclus.) or Ben Sira, is a work of ethical teachings, from approximately 200 to 175 BC, written by the Jewish scribe Ben Sira of Jerusalem, on the inspiration of his father Joshua son of Sirach, sometimes called Jesus son of Sirach or Yeshua ben Eliezer ben Sira.
In Egypt, it was translated into Greek by the author’s unnamed grandson, who added a prologue. This prologue is generally considered the earliest witness to a canon of the books of the prophets, and thus the date of the text is the subject of intense scrutiny. The book itself is the largest wisdom book from antiquity to have survived.
Canonicity
Sirach is accepted as part of the Christian biblical canons by Catholics, Eastern Orthodox, and most of Oriental Orthodox. The Anglican Church does not accept Sirach as protocanonical, and says it should be read only “for example of life and instruction of manners; but yet doth not apply them to establish any doctrine.” Similarly, the Lutheran Churches do not include it in their lectionaries but as a book proper for reading, devotion, and prayer. It was cited in some writings in early Christianity. There are claims that it is cited in the Epistle of James, and also the non-canonical Didache (iv. 5) and Epistle of Barnabas (xix. 9). Clement of Alexandria and Origen quote from it repeatedly, as from a γραφή, or holy book.
The Catalogue of Cheltenham, Pope Damasus I, the Councils of Hippo (393) and Third Council of Carthage (397) (397), Pope Innocent I, the second Council of Carthage (419), the Council of Florence(1442) and Augustine all regarded it as canonical
The Greek translation made by Ben Sira’s grandson was included in the Septuagint, the 2nd-century BCE Greek version of the Jewish scriptures used by Diaspora Jews, through which it became part of the Greek canon. The multiplicity of manuscript fragments uncovered in the Cairo Genizah evidence its authoritative status among Egyptian Jewry until the Middle Ages.
Because it was excluded from the Jewish canon, Sirach was not counted as being canonical in Churches originating from the Reformation, although they retained the book in the Apocrypha.
–Wikipedia
In short, because the churches accepted Sirach as canonical based on its inclusion in the Jewish authoritative translation of the Old Testament into Greek (the LXX – Septuagint), the Jews, after Christ, rejected it in their canon. Then, because the Jews rejected it based on the churches’ inclusion of it, based on the Jews’ previous inclusion, the Protestant churches rejected it. The Protestants followed the Christ-hating Jews in nearly every point regarding the Old Testament, just to oppose the Catholic Church on as many issues as possible. Later, with the rise of the Sciences surrounding manuscripts, the Protestants, dominating the field, established whatever reasoning they could to support their ongoing rebellion, for the sake of rebellion. By this, I am not advocating a return to the Catholic Church, nor am I condoning ungodly practices that were common at the time of the Reformation. My evaluation is of the behavior of the Protestants with regards to obeying Scripture. As for Sirach, it was a casualty caught in the crossfires. I, therefore, advocate restoring it to canonical status, as it has enjoyed among the most ancient churches.
Here is the 1st chapter of Sirach. The book has a total of 51 chapters. You can read them all here.