St. Nilus was a skilful calligrapher and practised his art with ability and elegance: he was also the inventor of a special abbreviation system (tachygraphy) and gave rise to a peculiar writing school, the 'nilian' school. Three manuscripts written personally by St. Nilus are preserved: they contain some monastic writings of the patristic age.

Some of the disciples of Nilus were scribes too: the nilian monks went on copying manuscripts until the end of the XIIIth century; they wrote chiefly liturgical and, in a lesser extent, ascetical manuscripts. With the addition of both purchased and inherited manuscripts the most ancient nucleus of the library was formed.

During the centuries the library had to suffer from various vicissitudes. Many manuscripts were transferred to Roman libraries such as the Vatican or the Angelica, but many others were bought too: among the latter a precious copy of the Byzantine epic Digenis Akritas (Xth cent.). In the second half of the XVIth century a new period of manuscript writing began.

The library owns also a good number of rare palimpsests, i.e of old parchment manuscripts whose first script has been erased in order to have the possibility of using the parchment for a new script: with the modern technical tools it is now possible to read anew the former script and to recover the lost work.

In 1873 the library, together with all of the abbey buildings, was confiscated by the recently formed Italian State.

The library has at the present time about 500 Greek manuscripts and more or less as many Latin manuscripts, some hundreds of incunabula and XVIth century editions, and 50.000 printed books.

The monastic community has a library of its own, counting about 20.000 books.

high monk Matteo Criptoferritis