They are books, written in Second Temple times, that the Catholic
churches (both Roman and Eastern) accepted as part of the Bible,
but the Protestants rejected. The best known book of the apocrypha,
which is quoted in the Talmud, is the book of Ben Sira. "Apocrypha"
means "hidden". Some of the apocryphal books may represent authentic
Jewish traditions, but others may have sectarian origins.
We now have almost all of the Hebrew original of Ben Sira, but most of the apocrypha have survived only in other languages such as Greek, with only hints in their word usage to tell us that they were originally written in Hebrew or Aramaic.
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