It's a realistic portrayal of a drunken old man, unkempt and scruffy, unshaven, badly dressed, his hat askew. He is probably already drunk. But there's no moralising here. There is, about his expression, the way he holds our gaze, something entirely engaging. This man looks as though he is probably good fun, at least in small doses. He has had an interesting life, you feel, and he'll happily tell you about it, embellishments and inventions and all. It is a quietly powerful piece of painting.
And more, as a piece of storytelling it is exemplary. You look at this man and his life unfolds before you. To be able to conjure someone so realistic should be the aim of any creative writer.