Caravaggio's great painting The Taking of Christ is dominated by a long arm of the law – that of an armour-plated Roman soldier reaching out to arrest Jesus. But as I had never quite noticed until the picture's latest exhibition at the National Gallery, the long arm distracts from an unfeasibly short one, belonging to Judas, immediately behind it.
Judas’s arm begins, as is normal, at the shoulder, visible just above the Roman’s. Then it becomes temporarily eclipsed behind the soldier’s elbow.
Beyond that it reemerges, crucially, to lay a betraying hand on Jesus. But as with a too-hurried plot denouement, there seems to have been something missing. The hand and shoulder are too close together to be believable.
By way of perspective, the NGI show – "Beyond Caravaggio: the Dark, the Light, the Drama" – juxtaposes The Taking of Christ with the artist's equally famous The Supper at Emmaus, on loan from the UK's National Gallery.
That features a swaggering display of draughtsmanship, with the side-on apostle on Jesus’s left throwing his arms wide, into and out of the picture, while the one with his back to us hunches his shoulders and elbows on a different, diagonal plane.
But in The Taking of Christ, Judas reaches across the frame, with no excuse for foreshortening. So is this the artistic equivalent of a typo, or is it I who am missing something? Could it be that the artist had his own good reasons for doing it as he did?
No, apparently. According to Sergio Benedetti, the now-retired curator who was central to the picture's rediscovery as a Caravaggio, it was probably just bad planning. As quoted in Jonathan Harr's The Lost Painting (2005), Benedetti said: "It looks like he painted the shoulder and then didn't have enough room for the arm".
Oh well. Everyone makes mistakes, it seems – even geniuses at the peak of their powers. Caravaggio shocked the conservatives of his era by having too much humanity in his religious figures (they called his style “naturalism” at a time when that wasn’t a compliment). Clearly, the frailty was not limited to his models.
If he was in too much of a rush to correct the Judas error, his own troubled relationship with the law may have been to blame. Like Byron, but with the possible excuse of lead poisoning, Caravaggio was mad, bad, and dangerous to know. For this reason, among those he was known to – as crime journalists say – were the police.
In The Taking of Christ, as was his wont, he put himself in the picture, as the lantern-holder behind the soldiers. This, however, was the reverse of his usual position regarding the law. After several visits to prison, he spent his last years as a murderer on the run. And although it was probably the lead that claimed his life, at 38, he wasn't short of enemies who might have been intent on foreshortening him, one way or another.
Happily for art, Caravaggio did enough in his brief heyday to attract followers of a non-policing kind too. Hence the NGI show, which is not just about him but about the generation of artists for which his lantern lit the way.
Among those featured is Gerrit Von Honthors, best known from the great latter-day detective case in which Benedetti, and others, worked out that a long-missing Caravaggio was leading a secret life, under an assumed name, in Dublin.
But the exhibition also touches upon at least one other mystery, fascinating to historians of the “tenebristes” (“shadowists”), as Caravaggio’s followers were known. It used to be thought that this posse included both a Frenchman named Tromphime Bigot, born in Arles in 1579, and a man of uncertain origin known as “The Candlelight Master”, who was active in Rome in the 1620s.
Their styles were similar, but different in important ways.
So even though the Candlelight Master’s Italian records suggested a link, the evidence was otherwise as silent as the “t” in Bigot.
One theory was that the two men were father and son. Not until the 1980s did investigators find documents that proved the Arlésien had gone to Rome in his 40s, his style presumably evolving there to suit the local market.
Even today, however, some Italian galleries hedge their bets, hanging the paintings as if by different artists.
But in displaying a work entitled Christ in the Carpenter's Shop, which is simultaneously credited to The Candlelight Master and "possibly" Bigot, the NGI has edged towards closing the case.