If you haven’t yet been to Sacred, the British Library’s display of religious manuscripts, go. It is a stunning exhibition of some of the oldest and most beautiful texts in Judaism, Christianity and Islam, shown side by side in all their complex, intricate glory. The idea was to show how much the three faiths have in common. And they really do.

For they are all religions of the Word, “peoples of the book”, faiths that believe that God who created the Universe did not hide His purposes in silence. He spoke to those humble enough to listen. They taught those words to others and preserved them in sacred texts which became their most precious possession: the Hebrew Bible, the Old and New Testaments and the Koran.

Here they are, displayed together: a fragment from the Dead Sea Scrolls, ancient versions of the gospels including the only remaining copy of a composite narrative written by Tatian, a 2nd-century Christian, and a Koran written in Arabia within a century of the Prophet’s lifetime.

What you see immediately is the creative interplay between the faiths in earlier times. They learnt calligraphy, design and illumination from one another. Ancient Torah scrolls, the elaborate capital letters of the Lindisfarne Gospels, and the rich geometric patterns of Islamic texts each sends forth ripples of resonance and imitation in the other faiths. At times the illustrations look like direct copies. King David looks suspiciously alike in two 13th-century French texts, one Jewish, one Christian.

And this is only the surface of what was in fact a much deeper web of reciprocal borrowing. Jewish law, Halakhah, influenced Sharia, its Islamic counterpart. The great Muslim philosophers of the 11th and 12th centuries introduced the thought of Plato and Aristotle to Jewish sages such as Maimonides, who in turn influenced Aquinas. The Jewish poetry of medieval Spain owed much to Arabic verse. The encounter with Christianity stimulated Jewish Bible commentary. The strands interweave, forming unexpected patterns.

But there is another story about which the exhibition is silent. Ages of tolerance, what the Spanish called convivencia, were short. This struck me when I saw a rare, beautiful and lavishly decorated Hebrew manuscript: the Lisbon Bible of 1482.

Look at it and you see a settled Jewish community, able to commission works of craftsmanship that must have taken years to make.

Yet within ten years, Jews and Muslims had been exiled from Spain, and five years after that they were driven from Portugal. It was the sudden, brutal end of medieval Jewry’s golden age.

Religion, I constantly have to emphasise these days, has no monopoly on bloodshed. French revolutionary terror, Nazi Germany and Stalinist Russia, secular systems all, were far more murderous. The issue has nothing to do with faith and everything to do with our inability to recognise the human dignity of those with whom we disagree. I sometimes worry whether we might be living in another 1482, a time of economic growth and affluence, but one in which you have to be deaf not to hear the distant thunder of civilisational conflict. That is when libraries and ancient manuscripts become terribly important. If we forget the past, we may repeat it.

We need Jews, Christians and Muslims prepared to bring together what the winds of globalisation are driving apart. One such figure was the late Dr Zaki Badawi, a generous role model of moderate Islam. Another is Akbar Ahmed, whose forthcoming Journey into Islam tells the story of his search for tolerance within, and dialogue between, faiths.

Look at these manuscripts in the British Library and ask yourself: if the rabbis, priests and imams who cherished them could only have seen them side by side, as we do now, would they not have recognised that however different, they share a loving devotion to the sacred word.

Rabbi Sir Jonathan Sacks is the Chief Rabbi of the United Hebrew Congregations of the Commonwealth

Sacred is in the Pearson Gallery at the British Library, London, until September 23; admission free – advance booking recommended