Saint Francis's enduring appeal on display at National Gallery

Borrowing from Islamic practice

Later, Pope John Paul II drew on this episode to underline the importance of ecumenical understanding between the monotheistic religions.

Near the painting hangs a relic from the trip brought back to the West, an ivory horn given as a gift by al-Kamil. The inscription tells us that Francis did more than show respect for Islam. He also borrowed an Islamic practice and blew on the horn to summon his followers to prayer.   

It's fair to say that Francis was no easy person to have chosen a gift for. What does one give a man who has nothing?

Basing his philosophy on the Sermon on the Mount, he famously renounced the wealth he had been born into, renounced his father, even tore off his expensive clothing and went around in coarse habits, an example of which is displayed here.

Saint Francis was said to have fallen in love with Lady Poverty to whom he was devoted all his life. He is also credited with one of the first works of literature to be written in the vernacular, known as the canticle of the Sun. 

Now, of course, it is Dante Alighieri who usually gets the credit for this innovation, the same poet who devoted his Divine Comedy to the chaste admiration of Beatrice, a young Florentine girl.

Enchanted by the story of Francis as his contemporaries, it's probable that when he sets his discussion of the saint in the passage of the Paradiso devoted to the Sun, it is the canticle he is alluding to.

Centuries of fascination

The long centuries of fascination with Francis have led to changes in emphasis.

In the wonderful depiction by Sassetta, there is as much interest in an episode in Gubbio when Francis managed to tame a wolf that had been preying on the townsfolk – a notary is present to record the wolf's earnest protestations of good behaviour – as there is in the moment when Francis receives the five wounds of Christ, known as the stigmata.

Though we see another, late version of the wolf, this time with a halo, the Counter-Reformation tended to emphasise the mystical aspect of his story.

In one room, we see him with a skull at his feet in Bellini's ambitious painting – his humble sandals rendered in sharp detail – while on the other side of the space El Greco has him gazing, watery-eyed, at the heavens. Again, there's a skull, this time on a table. The saint displays the holes in his palms.

Distaste for riches

At the end of the room, we see him embracing Christ and deftly kicking a large globe away with one foot, in a rejection of worldly things. Francis was not against work as such, but he condemned money.

This distaste for riches could have got him into trouble with the church, but unlike the Cathars, also ascetics, Francis didn't dabble in theology.

It is in the room with the birdsong that the curators remind us of the lighter side. A picture by Stanley Spencer has a genuine Franciscan charm. Spencer used his father (who is wearing eccentric slippers and a rope round his waist) as the model for Francis.

Rather than preaching, he appears to wander absent-mindedly out of the frame stage right, followed by a troop of birds including geese and chickens, while on the rooftop behind there are more hens and the odd dove. They do not toil, neither do they spin.

In other versions of the sermon, it appears that Francis has brought about peace among the birds – hawks and doves are reconciled. Spencer's Francis may be too old.

Nonetheless, while Sassetta's notary and penitent wolf capture the quaint folklore aspect of his story, only Spencer manages to evoke the saint's naïve gentleness.

'Saint Francis of Assisi' is free and can be seen at London's National Gallery until 30th of July.