Of particular importance is the CODEX SINAITICUS SYRIACUS, a palimpsest manuscript famous for its fifth-century underwriting. Still visible on the parchment is the earliest text of the New Testament Gospels in Syriac.

The monastery also retains a number of folios and fragments from the fourth-century CODEX SINAITICUS. This manuscript contains the earliest complete text of the New Testament in Greek. The rest of the codex was fraudulently removed from Sinai in the 19th century by a German scholar, who presented it to the Russian tsar. Joseph Stalin later sold it to the British Museum, and it is now on display in the British Library, although the monastery has requested its return.

In addition to the texts, the Saint Catherine’s Library preserves the largest single surviving accumulation of Byzantine bookbindings. The Syriac and Arabic manuscripts represent a remarkable, virtually untouched, collection of early manuscripts in their original bindings.

The collection of early printed books includes finely printed Greek texts from most of the major European printers. Some are in fine bindings and others are in even rarer contemporary interim bindings in parchment and paper.