St John the Baptist at the Fountain, in a private collection in Malta, is difficult to gain access to and consequently few scholars have been able to study it.
John Gash treats it as by Caravaggio, pointing out the similarity in the treatment of the flesh to the Sleeping Cupid, recognised as by the artist and dating from his Malta period.
The painting has been badly damaged, especially in the landscape.
The work is known in two other variants, each slightly different.

The theme of the young John drinking from a spring reflects the Gospel tradition that the Baptist drank only water during his period in the wilderness.
The painting displays typically Caravaggist extreme chiaroscuro (use of light and shadow), and is also typical in taking a young John the Baptist as its subject, this time set in a dark landscape against an ominous patch of lighter sky. "
The mechanics of drinking and the psychology of thirst are beautifully conveyed through the artful manipulation of limbs and the carefully constructed head".

If it is in fact by the artist, it would have been painted during his approximately 15 months in Malta in 1607–1608.
His recognised works from this period include such masterpieces as  the Portrait of Alof de Wignacourt and his Page and The Beheading of Saint John the Baptist.
The latter, in the oratory of the Co-Cathedral of Saint John, is the only work that the artist signed.

In Malta Caravaggio was accepted into the Order of Saint John (the Knights of Malta) and became in effect their official artist, but his stay ended with a mysterious offense and his expulsion from the Order "as a foul and rotten limb".
The crime on Malta has been the subject of much speculation, but seems to have been extremely serious, possibly even involving the death penalty.
Most modern writers believe that it was a crime of violence.
His earliest biographer, Giovanni Baglione, said that there had been a "disagreement" with a knight of justice (i.e., a knight drawn from the European nobility); Giovan Pietro Bellori, who visited Malta to see the Beheading of John the Baptist some fifty years after the event, wrote that Caravaggio "had come into conflict with a very noble knight", as a result of which he had incurred the displeasure of the Grand Master and had to flee.
It is possible that the offence involved a duel, which was regarded very seriously – but the penalty for duelling was imprisonment, not death.
The death penalty was imposed for murder – and a death in a duel or brawl equated to murder – but the wording used by both Baglione and Bellori implied that the knight Caravaggio offended had survived.
Peter Robb, in his popular biography M, (1998), makes the case for a sexual misdemeanour, but his argument is speculative.
St John the Baptist at the Fountain, in a private collection in Malta, is difficult to gain access to and consequently few scholars have been able to study it. John Gash treats it as by Caravaggio, pointing out the similarity in the treatment of the flesh to the Sleeping Cupid, recognised as by the artist and dating from his Malta period. The painting has been badly damaged, especially in the landscape. The work is known in two other variants, each slightly different.
The theme of the young John drinking from a spring reflects the Gospel tradition that the Baptist drank only water during his period in the wilderness. The painting displays typically Caravaggist extreme chiaroscuro (use of light and shadow), and is also typical in taking a young John the Baptist as its subject, this time set in a dark landscape against an ominous patch of lighter sky. "The mechanics of drinking and the psychology of thirst are beautifully conveyed through the artful manipulation of limbs and the carefully constructed head".
If it is in fact by the artist, it would have been painted during his approximately 15 months in Malta in 1607–1608. His recognised works from this period include such masterpieces as  the Portrait of Alof de Wignacourt and his Page and The Beheading of Saint John the Baptist. The latter, in the oratory of the Co-Cathedral of Saint John, is the only work that the artist signed.
In Malta Caravaggio was accepted into the Order of Saint John (the Knights of Malta) and became in effect their official artist, but his stay ended with a mysterious offense and his expulsion from the Order "as a foul and rotten limb". The crime on Malta has been the subject of much speculation, but seems to have been extremely serious, possibly even involving the death penalty. Most modern writers believe that it was a crime of violence. His earliest biographer, Giovanni Baglione, said that there had been a "disagreement" with a knight of justice (i.e., a knight drawn from the European nobility); Giovan Pietro Bellori, who visited Malta to see the Beheading of John the Baptist some fifty years after the event, wrote that Caravaggio "had come into conflict with a very noble knight", as a result of which he had incurred the displeasure of the Grand Master and had to flee. It is possible that the offence involved a duel, which was regarded very seriously – but the penalty for duelling was imprisonment, not death. The death penalty was imposed for murder – and a death in a duel or brawl equated to murder – but the wording used by both Baglione and Bellori implied that the knight Caravaggio offended had survived. Peter Robb, in his popular biography M, (1998), makes the case for a sexual misdemeanour, but his argument is speculative.
John the Baptist (Caravaggio)