Presented by an abbess to her convent of nuns, a medieval tome known as the Liesborn Gospel Book is one of the most valuable gospels on the planet.

Only five copies with rare first pages are known to exist, and now one has revealed an extra hidden treasure – a mysterious hand-drawn prayer wheel inside.

But despite the unusual find, it is not known how to use the enigmatic diagram.

A page in a rare medieval tome named the Liesborn Gospel Book bears a mysterious prayer wheel, but how it was used remains a mystery. It has concentric circles bearing quotations from the Lord's Prayer and gifts of the Holy Spirit

The book, containing just the Gospels of Matthew, Mark, Luke, and John, has a cover made of carved oak with copper clasps and is thought to have been ordered by an abbess - or female superior - called Berthildis for highborn ladies who entered her convent in Liesborn in Germany.

The book is for sale by Manhattan-based medieval manuscripts dealer Les Enluminures Gallery for $6.5 million (£4.3 million).

The mysterious prayer wheel was likely added to the book’s blank first page in the 12th century.

The tome was primarily used for display and oath taking and was considered to be sacred and the physical embodiment of the Word of God.

Only five copies with rare first pages are known to exist, and now one has revealed an extra hidden treasure – a mysterious hand-drawn prayer wheel inside. This image shows an English translation of the medieval Latin original, written in red and black ink

THE LIESBORN GOSPEL'S IMPRESSIVE APPEARANCE AND SIGNIFICANCE Throughout the Middle Ages, Gospel Books were considered the physical embodiment of the Word of God. They were kept in churches as sacred objects and carried ceremoniously to the altar during mass. The importance of such books was often displayed in elaborate treasure bindings often containing gold, gemstones and relics. The binding on the Liesborn Gospels shows an image of the Crucifixion carved into a thick piece of oak and is a late 15th century replacement of an earlier treasure binding. Four symbols of the evangelists are shown in each corner: an angel for Matthew, an eagle for John, a lion for Mark ans a winged ox for Luke. The cover was originally painted in gold, red, blue and 'flesh' colours, but only the striking blues and reds remain. The lower cover is in brown leather, decorated with stamps including impressions of the Virgin Mary standing on a sickle moon, holding Jesus, and the Lamb of God. 'A treasure binding constructed from a wooden relief carving is certainly exceptionally rare and may be unique,' the seller's documents say. This Gospel Book is one of the few surviving manuscripts from this time period from North western Germany, and the only manuscript from the diocese of Münster. Advertisement

A copy of the tome complete with its painted wooden cover showing the crucifixion is listed on the seller's website. It's said to be in 'astonishing condition as it has been treasured for a thousand years and bound for six hundred in a 'binding of extreme significance'

The book, containing just the Gospels, has a cover made of carved oak with copper clasps and is thought to have been ordered by an abbess - or female superior - called Berthildis for highborn ladies who entered her convent in Liesborn in Germany. The leather back is shown left and an illuminated page, right

Written in Latin and arranged in concentric circles, the prayer wheel’s outermost ring contains instructions, which when translated from medieval Latin read: ‘The order of the diagram written here teaches the return home.’

CIRCLES OF THE PRAYER WHEEL The wheel's outermost circle contains instructions that when translated, read: 'The order of the diagram written here teaches the return home'. The next reads 'seven petitions' and features seven quotations from the Lord’s Prayer along its spokes. The third circle from the outside reads ‘Gifts of the Holy Spirit' and includes the words ‘wisdom’ and ‘counsel,’ written in a mixture of black and red ink. It also includes seven events in the life of Jesus, which are written in black. The innermost ring lists the seven groups of people blessed in Jesus’ Beatitudes. And the centre contains the word Deus, or God. The wheel was originally written in medieval Latin. It appears as if a user would have worked their way to the centre either reading the rings in turn, or working along the prayer wheel's spokes. But how it is meant to be used and its intention is a mystery. Advertisement

The next circle, entitled 'seven petitions', contains seven quotations from the Lord’s Prayer along its spokes, including ‘daily bread’ and ‘kingdom come'.

The third circle from the outside reads ‘Gifts of the Holy Spirit,’ and includes the words ‘wisdom’ and ‘counsel,’ written in a mixture of black and red ink.

Written in red, these gifts are mixed with seven events in the life of Jesus, such as his baptism and ‘passion day of judgement,’ which are shown in black.

Around the centre of the wheel, which reads Deus, or God, are the seven groups of people blessed in Jesus’ Beatitudes, for example, the meek and poor of spirit, with their rewards, such as ‘inherit the Earth’ and ‘Kingdom of heaven’ listed opposite.

The diagram is an early example of its kind, which is known in five other manuscripts, the earliest of which is an 11th century work from south western Germany.

While the contents of the wheel will be familiar to modern Christians, how it was used, perhaps by medieval nuns, is a mystery.

Lauren Mancia, an expert at Brooklyn College who has studied the Liesborn Wheel, told Religious News that monks and nuns in Central Middle Ages had a bad reputation for learning prayers and mumbling them without thinking.

But ‘this diagram suggests that they’re not just mumbling, they’re using a mnemonic device to remember and internalise, or even to make an inner journey,’ she said.

It resembles diagrams used by religious people to organise their thoughts centuries later, or may even looks like a magical incantation to some.

It appears as if the wheel can be used in two main ways, so that a reader could think about the words in each concentric circle, working towards the middle, or follow each ‘spoke’ of the wheel to focus their prayers. A page of text from the Gospel of Luke is pictured above

The wheel questions the notion that monks and nuns in the Central Middle Ages simply learnt prayers by rote instead of embarking on a spiritual journey. This image from a 13th Century painting shows monks and nuns welcoming travellers and caring for the sick

WHO WROTE THE BOOK? It's not known precisely who produced the book, including all the scribes and the maker of the elaborate cover. However, the second scribe signed his name, Gerwardus, in simple code, at the bottom of page 337 replacing vowels with consonants. A translation of the signature reads: 'The deacon Gerwardus wrote this book in the first year of his ordination.' It's very unusual for any Gospel to be signed, and the code hints that either the deacon wanted to demonstrate some humility, or his cleverness. Each Gospel begins with a decorative page including a combination of illuminated capitals drawn in red and in filled with pale yellow and occasionally touches of green. This type of text mimics traditions established in the ninth century. It's a solemn volume because of its lack of lavish gold and silver pigment, or bright colours and illustrations, so the readers focus on the text itself. Experts know the text was written near the end of the 10th century, because of its upright, broadly spaced style and other stylistic details. Advertisement

It appears as if the wheel can be used in two main ways, so that a reader could think about the words in each concentric circle, working towards the middle, or follow each ‘spoke’ of the wheel to focus their prayers.

It’s not known whether the diagram was used to teach people or was private aid for meditation, - or whether it was an exercise designed to be repeated again and again.

It appears that the volume is missing the page before the one including the diagram, which raises the tantalising question of whether there were once instructions of how to use the wheel, or whether nuns who came across it were as clueless as we are today and chose to use in unique ways.

The importance and use of Gospels at the time however, is well known.

Public reading of the Gospels was part of the church's liturgy from the early days of Christianity and by medieval times, there were typically at least two readings in every mass.

The second was the most important and always from one of the four Gospels.

The final text in the Linsborn book is a list of mass readings for the liturgical year, allowing devout Christians to find the correct passage within the large tome.

The last and only time the rare manuscript appeared in a bookseller’s catalogue was in 1945, when it was described as ‘one of the most valuable manuscripts of the gospels in private hands,’ Fine Books Magazine reported.