Religious beliefs seem so often to be all about squabbling. At best we spend our time bickering about headscarves or hygienic habits; at worst we descend into terrible wars. And yet, for all the intolerant spats that scar our society, the three Abrahamic faiths by which our civilisation was moulded have since their beginnings had an awful lot in common. This is the message that becomes progressively more emphatic as you study the important collection of manuscripts on display in Sacred , a magnificent new British Library exhibition of some of the world’s most exquisitely beautiful books.

This show takes as its basis the sacred texts fundamental to Judaism, Christianity and Islam, the three monotheistic religions that have informed so much of our history. Perhaps for the first time, their holy writs are compared and contrasted side by side.

British Library curators can draw on rich resources. An unparalleled archive includes treasures that range from papyrus scraps rescued from an Egyptian rubbish dump to the most sumptuously ornamented of manuscripts. These are supported by loans of key texts from other museums, including a Dead Sea scroll fragment (one of several pieces never before shown in this country), and by objects from private collections, from an exquisite silver set used during the Jewish ceremony of Passover through the richly decorated curtain that once hung over the door of the Kaabah (the cube-shaped stone structure in the Grand Mosque in Mecca that forms the focal point of all Muslim worship) to the shalwar kameez that Jemima Khan wore at her wedding.

But at the heart of the show are the manuscripts: those most precious survivors of centuries of pogroms and wars and oppressions, of years of neglect and accident. To- gether they tell a story as vividly intriguing as psalter illuminations, as intricately complex as an Islamic carpet, as minutely detailed as the masoretic notes that weave their patterns around the writings of a Jewish Pentateuch.

The more ostentatiously dramatic of these texts seem more like objects than mes- sages, more like spiritual icons than mere books. Admire the wonderful calligraphy on a leaf of the Lindis-farne Gospels, for instance. This manuscript was far more than a practical text. Transformed by the artistic talent of its maker, it attained a symbolic power. It was not there to be read. It was meant to be glimpsed from a reverent distance by those who queued up to bear witness to this piece of solid proof of Christianity’s strength. Jewish scriptures took on a similar totemic importance. They became a sort of substitute for the Temple of Jerusalem after it was razed by the Romans in AD70. “Where two or three study the Torah together,” explained the rabbis, “the Shekhinah [divine presence] is in their midst”.

And yet, for all that Jews, Christians and Muslims have searched for some embodiment of the sacred in their holy texts, these scriptures remain an open book. There is no such thing as one Judaism, one Christianity or one Islam. There is no monolithic scripture with a single divine meaning. From the beginning, when word-of-mouth stories were first written down by people with dodgy memories and vivid imaginations no doubt, they have been interpreted.

Different authors have contributed their own versions; stories have been added and subtracted, approved or discredited. Voices argue and compete. Translations alter and adapt. Even the Koran, though something of an exception — it was compiled by Muhammad’s followers a few years after the Prophet had received his divine revelations and had been definitively codified before some 20 or 30 years had passed — is open to endless exegesis. In this British Library show the pieces of the jigsaw that men have been puzzling over for centuries are laid out chronologically upon pieces of papyrus or parchment or paper. But it remains a complex jumble that will never be completed.

On a basic level the exhibition is instructive. It explains the differences between Sunni and Shia Muslims, for instance, or between Ashkenazi and Sephardic Jews. It explores such debates as that concerning figurative representation, whether the depiction of the divine is acceptable (an argument which encompasses in its course an extremely rare Jewish representation of God). But the scriptures, in the end, always seem to raise more questions than they answer. It is their astonishing diversity that is stressed — and perhaps most of all in the case of Christianity, possessed by an almost feverish tendency for division and subdivision into denominations and sects. Here are its scriptures, for instance, as they were presented in anything from Armenian through Georgian or Coptic, Samaritan and Syriac to the Walton Polyglot Bible compiled in the 17th century in no fewer than nine languages. Here is a Torah scroll from 17th-century China or, a century later, a Hebrew psalter in Ethiopic script. The Koran may be a single text, but it is inscribed in anything from Iraq’s Kufic calligraphy through the Bihari style of India to the nastaliq script that was developed in Persia.

This show emphasises a sprawling cultural diversity as artists bring their own local traditions and distinctive interpretations of the ancient scriptures. Henry VIII, complete with garter and codpiece, strums the harp in the guise of David in one illustration from his cus- tomised psalter, while an Ethiopian Gospel presents the Temple of Jerusalem as some local church with a pair of ostriches roosting in place of the more usual peacocks.

And yet, even amid the endless adaptations and diversifications (and even with the occasional religious attack), it is the common links that emerge most emphatically. The biblical Joseph is hon-oured as a prophet in Islam, as a beautifully illuminated Malay version of the Koran attests. Jews and Christians work side by side as local artists ornament Hebraic scripts with the flora and fauna of their countryside. A 9th-cen-tury Egyptian manuscript shows the psalms presented with the panache of Islamic calligraphy. The tradition for decorating scriptures with strange and rare marginal creatures is shown developing side by side in both Jewish and Christian texts.

Some of the most fascinating displays are the most visually unappealing. A page of inscrutable scribbling, it turns out, is the Diatessoron — an attempt to combine the four Gospels into one narrative account that was so ruthlessly suppressed that no single complete manuscript sur- vives. And yet curators are keen also to show off their most exotic treasures, the most sumptuously ornamental of their manuscripts. Here are Korans in pure sweeps of burnished gold, Hebraic texts scrolled about with extravagant creatures, Christian stories illuminated with a vig-our that brings them springing to life.

Through exquisite creations that mirror, in some way, the wonders of a supreme deity, artists of all religions seem to seek to embody their sense of the holy. We look at these books, earthly symbols of divinity, and discover a sacred beauty which, even in our modern age, we can all share.

Sacred is at the British Library, London NW1 (020-7412 7332, www.bl.uk), from Friday

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