What was the black-winged god of desire? The insights that masterwork reveals about the rogue genius

The youthful boy screams while his skull is firmly gripped, a large digit pressing into his cheek as his father's mighty hand grasps him by the throat. This scene from The Sacrifice of Isaac appears in the Florentine museum, creating unease through Caravaggio's harrowing portrayal of the tormented youth from the scriptural narrative. It appears as if the patriarch, instructed by God to kill his son, could break his neck with a solitary turn. Yet Abraham's preferred approach involves the silvery steel blade he grips in his other palm, ready to slit Isaac's neck. A definite aspect remains – whomever modeled as Isaac for this breathtaking work displayed remarkable expressive ability. There exists not just dread, surprise and begging in his shadowed eyes but additionally profound grief that a protector could betray him so completely.

He adopted a well-known biblical story and made it so fresh and raw that its horrors seemed to happen right in view of the viewer

Viewing in front of the painting, observers identify this as a actual countenance, an precise depiction of a adolescent model, because the identical youth – identifiable by his disheveled locks and almost dark eyes – appears in two other works by Caravaggio. In every instance, that richly emotional face commands the composition. In Youth With a Ram, he gazes playfully from the darkness while holding a lamb. In Amor Vincit Omnia, he smirks with a hardness acquired on Rome's streets, his black feathery wings sinister, a unclothed adolescent creating riot in a well-to-do residence.

Amor Vincit Omnia, presently exhibited at a British gallery, represents one of the most discomfiting masterpieces ever created. Observers feel totally unsettled looking at it. Cupid, whose arrows fill people with often painful desire, is portrayed as a very tangible, vividly lit nude figure, straddling overturned items that include stringed devices, a musical manuscript, plate armour and an builder's T-square. This heap of possessions echoes, deliberately, the mathematical and construction equipment scattered across the floor in Albrecht Dürer's engraving Melencolia I – except in this case, the gloomy disorder is created by this smirking deity and the mayhem he can unleash.

"Love sees not with the vision, but with the soul, / And thus is winged Cupid depicted sightless," wrote the Bard, just prior to this painting was created around the early 1600s. But the painter's Cupid is not unseeing. He stares straight at the observer. That countenance – sardonic and rosy-faced, looking with bold confidence as he poses unclothed – is the identical one that shrieks in fear in The Sacrifice of Isaac.

As Michelangelo Merisi da Caravaggio created his three images of the same unusual-looking kid in Rome at the start of the seventeenth century, he was the most acclaimed sacred painter in a metropolis ignited by Catholic revival. Abraham's Offering demonstrates why he was sought to decorate sanctuaries: he could adopt a biblical story that had been depicted many occasions before and render it so new, so raw and visceral that the terror seemed to be occurring directly in front of you.

However there existed another side to Caravaggio, evident as quickly as he came in Rome in the cold season that concluded the sixteenth century, as a artist in his initial twenties with no teacher or patron in the urban center, only talent and audacity. Most of the works with which he captured the holy city's attention were everything but devout. What could be the very earliest hangs in the UK's art museum. A young man parts his crimson mouth in a scream of agony: while reaching out his dirty digits for a fruit, he has instead been attacked. Youth Bitten by a Reptile is eroticism amid poverty: viewers can discern Caravaggio's gloomy room mirrored in the cloudy waters of the transparent container.

The boy wears a pink blossom in his hair – a symbol of the sex trade in Renaissance art. Northern Italian artists such as Tiziano and Jacopo Palma depicted prostitutes holding blooms and, in a painting destroyed in the WWII but documented through photographs, the master represented a renowned female prostitute, holding a posy to her bosom. The message of all these floral signifiers is obvious: sex for purchase.

What are we to interpret of the artist's sensual depictions of boys – and of one boy in particular? It is a inquiry that has divided his interpreters ever since he achieved mega-fame in the twentieth century. The complicated historical reality is that the artist was not the queer hero that, for instance, Derek Jarman put on film in his 1986 film about the artist, nor so completely devout that, as some artistic scholars unbelievably assert, his Youth Holding Fruit is actually a portrait of Jesus.

His early works do offer explicit sexual suggestions, or even propositions. It's as if Caravaggio, then a destitute young artist, identified with the city's prostitutes, offering himself to live. In the Florentine gallery, with this thought in consideration, viewers might look to another early creation, the 1596 masterwork the god of wine, in which the god of wine stares coolly at the spectator as he begins to untie the black sash of his garment.

A few years following the wine deity, what could have motivated Caravaggio to create Victorious Cupid for the artistic patron the nobleman, when he was at last becoming almost established with prestigious church projects? This unholy pagan deity resurrects the sexual provocations of his initial paintings but in a increasingly powerful, uneasy manner. Fifty years afterwards, its hidden meaning seemed obvious: it was a portrait of Caravaggio's lover. A British visitor saw Victorious Cupid in about the mid-seventeenth century and was informed its figure has "the physique and countenance of [Caravaggio's|his] own youth or servant that slept with him". The name of this boy was Francesco.

The artist had been deceased for about forty annums when this story was recorded.