Creature removed from manuscript by pious reader can be seen again using hyperspectral imaging, and will go on show as part of Bodleian Library exhibition

A demon lurking in the corner of a precious 17th-century Armenian gospel has reappeared centuries after he was deliberately scraped from the page by pious readers.

The creature is no longer visible to the naked eye, but once vied with the angel opposite him for the souls being weighed in the balance on judgment day, captured in the superbly illustrated gospel made by the renowned Armenian manuscript scribe, illuminator and theologian, Mesrop of Xizan, almost 400 years ago.

Hidden devil is revealed using hyperspectral imaging process. Photograph: Bodleian Libraries, University of Oxford

The demon will be revealed again by David Howell, head of conservation research at the Bodleian library in Oxford, using hyperspectral imaging as part of an exhibition of Armenian treasures. Opening on 23 October, it will mark the centenary of the attempted genocide of the Christian minority under the Ottoman empire, which scattered surviving Armenian families and their possessions across the world.

The Bodleian, one of the largest and oldest university libraries in the world, began collecting Armenian manuscripts in the 17th century, but many of the pieces are far older, including an 11th-century manuscript copy of John Chrysostom’s commentaries, and the only known copy of the first book printed in Iran, a book of psalms dating from 1638.

Another item on display, a matchbox-sized prayer book printed in Venice in 1831, has lengthy notes in frequently incorrect Mandarin, written in minute script by a former owner, the orientalist Solomon Caesar Malan who left his collection to the university. On one page he wrote “this is the wrong prayer”.

The exhibition will span more than 2,000 years of Armenian culture. Richard Ovenden, the director of the library, said the exhibition would have many objects of exceptional beauty.

“The Bodleian Libraries is honoured to take part in the commemorations for the 100th anniversary of the Armenian Genocide by helping to share the history and culture of the Armenian people,” Ovenden said.

A crimson silk altar curtain, embroidered in silver thread, was given in 1788 to the monastery of Surb Karapet in Taron, in present-day south-east Turkey. The monastery, founded in the fourth century, was destroyed after 1915.

As well as the spectacular manuscripts, the exhibition will include more humble objects precious to the Armenian families who have loaned them, including photographs and textiles. There is a lace collar that was made in 1890 for a donor’s grandmother, and a tattered copy of a book of mystical poems by Saint Gregory of Narek passed down through generations of the same family and believed to protect the household.

A samovar and a set of coffee cups and saucers – which traditionally were used for telling fortunes from the dregs after the coffee was finished – has been loaned by the Chalvardjian family. The history of the objects illustrates the wandering lives of many Armenians after 1915. They were first used in Cilicia – now southern Turkey – and then brought with the family to Milan, Cairo and then the UK. The samovar was made in Russia, but the cups and saucers completed a circuit, originally made for export in Staffordshire.