We are living through cuts to services and benefits that will disproportionately affect the poor. We have also seen a hysterical response to protest and dissent from some sections of society. Concern for the poor is a central theme in the life of St Francis of Assisi. He is a saint for our time, because he stands in a tradition of powerful demands for social justice. The problems he confronted head-on are all the problems we are grappling with right now: involvement in wars, poverty, corruption in high places, social exclusion and the wealth-poverty gap.

St Francis lived as one of the poorest and lowest in society, and worked as a day labourer. This was hard, menial, low-paid work, yet he never passed a collection plate when he preached, nor asked the public for money.

His life and message were uncompromising and simple: greed causes suffering for both the victims and the perpetrators. St Francis's views about the perpetrators are relevant as bankers award themselves enormous undeserved bonuses, while others suffer. The indifference of the greedy and their hatred of the poor hurts the rich, too: St Francis believed living with that sort of attitude was morally, socially and spiritually destructive.

Another problem St Francis grappled with was war. The people around him kept telling him he was mad to go single-handedly to stop the crusades. However, he got there and made a deep impression on the Muslim leaders, who, unusually, just let him go. Is it a hero or a madman who'd go to Afghanistan and try to stop the war there?

St Francis had no respect for people in high places, and when he walked to Rome and finally saw what the Vatican was like, he exploded. He publicly criticised the greed, wealth, power, venality, worldliness, corruption and emptiness of it all. Pope Innocent III could hardly believe his ears. Nobody had ever spoken to him like that, and here was this poor "nobody" telling him that the church was against Christ. St Francis was jailed for this outburst, but in the end the pope let him go. I suspect there are a number of people who would like to say this sort of thing to Pope Benedict today. In our own time, we see a similar problem with criticism at the seat of power and protest outside parliament, and might think of Brian Haw in this context.

St Francis's famous naked protest at the beginning of his ministry was especially forceful because his father was a cloth merchant, importing luxury fabrics. This initial naked protest was followed by further occasions of stripping off, in order to give his clothes to people poorer than himself. For St Francis, nakedness was not degrading, and he challenges us to look at ourselves as we gaze upon the naked and the hungry as we turn our backs on them.

He also played a proto guitar, which was an instrument some ecclesiastical authorities had condemned. He played his own songs and compositions and encouraged others to play this instrument to his famous Hymn to Brother Sun, which declares how our lives are all dependent on a common cause: our earth and the sun.

St Francis offers a vision of a different world, where we share more equally the abundant wealth of goods and life itself as we focus on the right relations to the earth and all our fellow creatures. His pantheist language, scruffy clothes and campaign for social justice are a good antidote to the toxic God images, body images and religious deification of wealth we struggle with today.