In the late 1650s Pieter de Hooch developed a type of genre painting that epitomizes what has come to be known as the Delft School. In such paintings, a group of figures is situated in a spacious, light-filled interior or courtyard. The architectural space is carefully defined, and the perspective recession of windows, ceiling beams, tiles, and bricks is accurately constructed. Figures, whether they be socializing around a table or occupied in domestic chores, tend to be set back in the space rather than situated in the foreground.
Vermeer's The Glass of Wine belongs entirely in this context. It is one of the clearest demonstrations of how he responded to the achievements of another artist. In this scene Vermeer depicted a spacious interior and set the figures back from the picture plane. Laws of linear perspective are rigidly and obviously followed. The subject of figures drinking around a table, and even the portrayal of a woman drinking from a glass, are taken from De Hooch. (http://www.johannes-vermeer.org/the-glass-of-wine.jsp)
One hand on a wine jug and the other on his hip, the cavalier patiently waits on the spectacularly dressed young woman ready to pour more wine as soon as it has been drunk.
Although rivers of ink have flowed to describe the beauty and decipher the thoughts and emotions of Vermeer's female sitters, the men who court them have received far less attention. Although they ought to be in control, in Vermeer's paintings it is always the female who, all said and done, commands the scene relegating the man to an oddly passive role.
This gentleman would not have been considered discourteous having kept his hat on. As Timothy Brooks observed, in the time this picture was painted "A courting man did not go hatless. The custom of removing one's hat while entering a building or greeting a woman was not yet observed. European only bared their heads before a monarch, and since the Dutch had no monarchs, their hats stayed on."
Marieke de Winkel, who has written extensively about Dutch costume in relation to painting noted that in the 17th-century Netherlands," the hat was perceived as a sign of authority and male supremacy. In contemporary French and Dutch language the word "hat" could be used as a metaphor for a man, as opposed to "coif" denoting a woman.
"German and English travelers in the Netherlands were frequently surprised that Dutch men kept their hats on indoors, during meals, in company and even in church. Members of the lower classes were required to remove their hats in the presence of superiors. Foreigners generally explained the Dutch disregard for 'hat honor' as their longing for egalitarianism, personal independence and freedom." (http://www.essentialvermeer.com/catalogue/glass_of_wine.html#.V9caooU43S9)