St Francis at the National Gallery (until June 30 2023)

Sassetta, Wolf of Gubbio, the San Sepolcro Altarpiece c.1440s, National Gallery, London

The National Gallery's small free exhibitions are always worth a visit. Sometimes, only a room and a couple of works - as with the recent Ugly Duchess or the newly opened Crivelli's Garden. Sometimes more substantial, like Sin which has been slowly touring the UK since it was shown in London in 2020, and is currently on view in Bishop Auckland. St Francis is idiosyncratic and thoroughly enjoyable. It takes you from the thirteenth century through to the present day, from holy relics and manuscripts to comic books and film. And yes, you won't like everything, but you'll also find unexpected joys.

The curators make judicious use of the gallery's own holdings. Their two wonderful Zurbarans are familiar but given space to breathe here. Never has poverty been so richly and lovingly expressed. The Sassetta sequence, despite being displayed against an unsettling mustard wall-colouring, is full of beautifully-realised detail. In The Wolf of Gubbio, a notary holds his quill poised in mid-air between delicate fingers, balancing a scroll on crossed legs. His face is alive with inner intelligence, but still his eyes widen at the miraculous sight before him. 

The first rooms are all about detail. The floral carpet which surrounds the flames in Fra Angelico's Trial by Fire; the marginalia of an English manuscript; the radiating phrases of Richard Long's Walk. Then you get the bigger picture: Baroque bombast. Caravaggio's early St Francis in Ecstasy has been heavily promoted, but for me the stand-out here is a clear, crisp El Greco. Every sinew of the grey-clad figure is visibly, vibrantly straining towards the surrealist-blue sky above.

I am less keen on Gormley's stigmatised, hollow, tin man: if he only had a heart. Similarly unemotionally-engaging is the HD, technicolour Victoriana. Cadogan-Cowper's 1904 St Francis is no match for the full-blown Pre-Raphaelite angel perched uncomfortably in a tree, or the sun-kissed Italianate landscape beyond. Merson's Wolf of Gubbio is precision perfect down to the last crack in the walls, but for that is as cold as the wintery scene streets if portrays. It's a relief to come back down to earth with Spencer's riotous, big-bearded, be-slippered saint. 

The last room, for all its pop culture contemporary interest feels like a weak ending. And worse, the exhibition throws away Buttner's 2016 Beggars woodcuts which in their simple, emotional punch take you right back to the Zurbaran at the start. But for all that, it's a great show which turns a thirteenth century saint into a man for all time, with a message for today.