He studied in Paris and in Cologne under the great philosopher St Albert the Great, at a time of great philosophical ferment, when the writings of Aristotle, the greatest philosopher of the ancient world, had been newly rediscovered and were becoming available to people in the West for the first time in a thousand years. Many feared that Aristotelianism was flatly contradictory to Christianity, and the fact that Aristotle’s works were coming to the West from mostly Muslim sources did nothing to help matters.

  Thomas’ clarity of thought ensured that the truth would be recognised whatever its source. He inaugurated a form of disputation which would bring ideas together not so that one would win and the other lose through clever tricks of debate, but so that the single unifying truth behind them should be found. He thus not only transformed the practice of theology but also laid the foundations of the modern scientific revolution.

  As well as producing major philosophical and theological works, Thomas, at the request of Pope Urban IV, composed the Divine Office for the newly-created feast of Corpus Christi.

  In the earliest centuries all vestments were white – the white of baptismal purity and of the robes worn by the armies of the redeemed in the Apocalypse, washed white in the blood of the Lamb. As the Church grew secure enough to be able to plan her liturgy, she began to use colour so that our sense of sight could deepen our experience of the mysteries of salvation, just as incense recruits our sense of smell and music that of hearing. Over the centuries various schemes of colour for feasts and seasons were worked out, and it is only as late as the 19th century that they were harmonized into their present form.