What was the black-winged deity of love? What secrets that masterpiece reveals about the rogue artist

The youthful boy screams as his skull is forcefully gripped, a large thumb pressing into his face as his father's powerful hand grasps him by the throat. This moment from The Sacrifice of Isaac appears in the Florentine museum, evoking distress through the artist's chilling rendition of the suffering child from the scriptural narrative. It seems as if Abraham, instructed by God to sacrifice his son, could break his spinal column with a solitary twist. Yet the father's chosen method involves the metallic steel blade he grips in his remaining palm, prepared to slit Isaac's neck. A certain aspect stands out – whomever modeled as the sacrifice for this breathtaking piece displayed extraordinary acting ability. Within exists not just dread, surprise and begging in his shadowed gaze but also profound sorrow that a guardian could betray him so utterly.

The artist took a well-known biblical story and transformed it so vibrant and raw that its horrors seemed to unfold directly in view of the viewer

Viewing in front of the artwork, viewers identify this as a actual countenance, an accurate depiction of a adolescent model, because the identical youth – identifiable by his tousled hair and nearly black eyes – features in two other paintings by Caravaggio. In every instance, that richly expressive visage dominates the composition. In John the Baptist, he peers playfully from the shadows while holding a ram. In Victorious Cupid, he grins with a toughness acquired on Rome's streets, his black feathery wings demonic, a unclothed child running chaos in a well-to-do dwelling.

Victorious Cupid, presently displayed at a London gallery, represents one of the most embarrassing artworks ever painted. Viewers feel totally disoriented looking at it. Cupid, whose darts inspire people with often painful desire, is portrayed as a very tangible, vividly lit nude form, straddling toppled-over items that comprise musical devices, a music score, metal armor and an architect's ruler. This heap of items echoes, intentionally, the mathematical and construction equipment strewn across the floor in the German master's print Melancholy – except here, the melancholic disorder is created by this smirking Cupid and the mayhem he can release.

"Love sees not with the vision, but with the mind, / And therefore is feathered Love depicted blind," wrote Shakespeare, just before this painting was produced around the early 1600s. But the painter's god is not unseeing. He gazes straight at you. That face – ironic and ruddy-cheeked, staring with bold confidence as he poses unclothed – is the identical one that screams in terror in The Sacrifice of Isaac.

When Michelangelo Merisi da Caravaggio created his multiple images of the identical unusual-appearing kid in Rome at the start of the 17th century, he was the most acclaimed sacred artist in a city ignited by Catholic revival. Abraham's Offering reveals why he was sought to adorn churches: he could adopt a biblical narrative that had been portrayed many times before and make it so new, so raw and physical that the horror appeared to be happening immediately in front of the spectator.

However there existed another side to Caravaggio, evident as quickly as he came in the capital in the winter that concluded the sixteenth century, as a painter in his initial twenties with no teacher or supporter in the urban center, only skill and boldness. The majority of the paintings with which he caught the holy city's attention were anything but holy. What could be the very earliest hangs in the UK's National Gallery. A youth parts his red mouth in a yell of agony: while reaching out his filthy digits for a fruit, he has instead been attacked. Youth Bitten by a Reptile is eroticism amid poverty: viewers can discern the painter's gloomy room mirrored in the murky waters of the transparent container.

The adolescent sports a rose-colored blossom in his hair – a emblem of the sex trade in early modern art. Venetian artists such as Titian and Palma Vecchio portrayed prostitutes holding flowers and, in a work destroyed in the second world war but documented through images, Caravaggio portrayed a renowned female courtesan, holding a bouquet to her bosom. The message of all these botanical signifiers is clear: intimacy for purchase.

What are we to make of Caravaggio's erotic depictions of youths – and of a particular boy in specific? It is a inquiry that has split his interpreters ever since he achieved widespread recognition in the 1980s. The complicated historical truth is that the painter was not the homosexual hero that, for example, Derek Jarman put on screen in his twentieth-century film Caravaggio, nor so entirely devout that, as some artistic scholars unbelievably claim, his Youth Holding Fruit is actually a portrait of Christ.

His initial paintings do make explicit sexual implications, or even propositions. It's as if the painter, then a penniless youthful creator, aligned with Rome's prostitutes, selling himself to survive. In the Florentine gallery, with this thought in mind, viewers might turn to an additional initial work, the 1596 masterpiece Bacchus, in which the god of alcohol gazes coolly at you as he begins to undo the dark sash of his robe.

A few annums after the wine deity, what could have driven the artist to create Amor Vincit Omnia for the art patron Vincenzo Giustiniani, when he was finally growing almost respectable with important ecclesiastical projects? This unholy pagan god revives the sexual challenges of his initial works but in a more powerful, uneasy way. Fifty years later, its secret seemed obvious: it was a portrait of Caravaggio's companion. A British traveller viewed the painting in about the mid-seventeenth century and was told its figure has "the physique and countenance of [Caravaggio's|his] owne youth or servant that slept with him". The name of this boy was Cecco.

The artist had been dead for about forty years when this account was documented.

Brian Walker
Brian Walker

A tech enthusiast and digital strategist with over a decade of experience in helping businesses adapt to technological changes.