"The young god is peering at us from over his glass of wine. Wine is the symbol of his power, and its surface ripples with movement as he offers it in his outstretched hand...He is no traditional god. From his drunken red cheeks, dark hands and dirty fingernails, to the sensual intent of the eyes and lips, he is a very worldly god, human even. [The model is taken to be a male prostitute.] The incredibly frank earthiness is one of Caravaggio's greatest innovations and achievements."
An earlier reference to wine here.