‘Tell him that learning and practice derived from study bring a greater understanding between us all. Let me give you an example – perhaps listening to an old Jew might allow you to impress him. Hundreds of years ago Hunain bin Ishaq al-Ibadi translated Hippocrates and Galen into Arabic. The original texts were lost so these were the only sources of medical literature in the Islamic period. Such a gift to us all is a blessing. Hunain was a heretical Nestorian Christian; I am a Jew. You hear those bells ringing for prayer in the town? Why do they ring at certain times of the day? Because the Christian Church followed the Jewish tradition of praying at the third, sixth and ninth hour and after midnight. The Christian prayer of that time comprised much the same elements as the Jewish: recital or chanting of psalms, reading of the Old Testament, and then the Christians added readings of the Gospels and epistles. The past holds us together and yet serves to tear us apart.’ Halif ben Josef rested a hand on Blackstone’s arm. ‘Let him learn about us all. I hope I might be privileged to meet him one day.’

‘I would be honoured. You have no children?’

‘Lost in childbirth, and then my wife herself was taken. And so I reach out to these young people.’ He looked to where the young Spaniard, Andrés, was attending to ben Josef’s horse and setting up a place for the elderly physician to rest for the night.

Blackstone’s eyes followed ben Josef’s. ‘The boy, does he live nearby?’ he asked.

‘The mountains, over there, but they are known to us here. He and his family live a harsh existence but they are good people, like the other peasants who bring their food to our market.’

Blackstone studied the terrain before darkness shrouded the mountains. The fertile valley was vulnerable from the surrounding peaks, most of which looked to be no more than two thousand feet high. ‘You’re safe here?’

‘As safe as anyone in these dangerous times. There are a hundred and eighty Jewish families over there among fifteen hundred Christians,’ said ben Josef. ‘The King protects us.’ He shrugged. ‘Thirty years ago the Christians in the town rose up and massacred many of us. The town was fined heavily and made to pay reparations and those who led the uprising were executed. A royal decree makes us his property, so he is responsible for us. For some years now we have lived in harmony with our Christian neighbours.’

‘And the castle?’ said Blackstone pointing to a rocky outcrop and imposing fortress in the distance.