The scene painted by Caravaggio shows a fairly young David in profile holding the head of Goliath, who has just been defeated, exactly as described in the sacred texts.
This version is earlier than the one in the Borghese Gallery and differs from the latter in several ways: first of all, the environment in which the scene is painted is slightly lighter than the Roman version, then the pose of the protagonists is different and Caravaggio’s self-portrait in the head of Goliath is not very similar but seems a generic face.
The boy depicted is very reminiscent of the one we saw in “Amor Vincit Omnia” also by Merisi, and according to research carried out by scholars, it would seem that this protagonist can be identified as Cecco del Caravaggio, a servant (and also an artist) of Caravaggio.