Loved or loathed, these men were on a mission from God

In 1540 the Society of Jesus, comprising St Ignatius Loyola and nine companions, was formally approved by Pope Paul III. By 1600, it had 8,500 members in 23 provinces. Ever since its foundation, it has been hugely influential in the field of education, founding and running some of the best schools in the world, in which many key figures, even today, were educated. It has almost 200 institutions of higher education in which more than 1 million students are being educated.

Even more remarkable is the Jesuits' record in mission work, obliged as they are to go anywhere that the Pope directs. Francis Xavier took the faith to India and Japan, Matteo Ricci to China, and other Jesuits to Canada, Brazil and Paraguay. Those who saw The Mission - with its unforgettable scenes of Jeremy Irons as a Jesuit climbing up beside a waterfall - will be familiar with the extraordinary towns of 5,000 or so Indians each run as a self-contained and prosperous welfare state under the control of one or two Jesuits.

Contrary to popular perception, the Jesuits were not founded to oppose Protestantism, but they were no less active in Europe in the Roman Catholic Church's own version of the reformation, with extended mission work, preaching engagements and spiritual direction, not least in the courts of the period.

Jesuits have, however, been loathed as much as they have been admired. In the 17th century, their theological understanding of the relationship between human free will and divine grace was attacked by the Jansenists and their too-relaxed view of ethics by Pascal. Their remarkable work in China, in which they were prepared to accommodate the Chinese reverence for the dead within an enlarged understanding of the communion of saints, was also strongly attacked.

They were expelled from one country after another and suppressed by the papacy in 1773. In 1814, however, they were reinstated and they have had an outstanding, sometimes heroic role in what Jonathan Wright calls the 5th Jesuit century: the 19th century and our own times.

Over the centuries, the order has produced some outstanding individuals in science, astronomy and almost every branch of human endeavour. Gerard Manley Hopkins was a Jesuit, as was Teilhard de Chardin.

Wright is sympathetic to the Jesuits, not least in our own time, but this book is a somewhat impressionistic history that focuses mostly on the way the Jesuits were perceived by others. There is a certain emphasis on gruesome martyrdoms and far-fetched miracles.

But how was it that this group of ten people managed so quickly to draw to itself the total, undeviating commitment of so many young men, and how have they kept that appeal over so many centuries? Why is it that they have been so successful and yet regarded with such suspicion?

At the heart of the Jesuit life are the spiritual exercises devised by St Ignatius Loyola, a particular way of meditating, using the imagination, which is still widely influential. Indeed, Ignatian spirituality has experienced something of a revival in recent times, with many people making both eight-day and 30-day retreats. I wonder about the relationship between this and the extraordinary, heroic endeavours of so many Jesuits. Wright does not really enter into this inner driving force, but he provides some lively examples of what Jesuits have done and how they have been perceived.

Richard Harries is bishop of Oxford.