“It starts from the mists of antiquity to end in Jesus Christ,” he explained. “You see on one side His ancestors after the spirit, on the other the Kings of Judah, His ancestors after the flesh. All the ages are there. And if you had looked more closely at what you took for scaffolds you would have been able to give names to the figures standing on them. At the feet of Moses you would have recognised the calf of gold, at Abraham’s the ram and at Joseph’s the demon counselling Potiphar’s wife.”