Purgatory – William Butler Yeats "Summary"

The boy and his father walk on the moonlight night; they are near a ruined house. Pointing towards the house, the old man describes the past of it. The house used to be occupied by his mother and her husband. The mother of the old man had married with the groom of the stable as soon as she met him. The man later turned out to be a drunkard and gambler. Due to drinking and gambling, he emptied everything he had. The mother died while giving birth to him. 

The father continued his misdeed, which at last resulted into the complete destruction of house. Because of fear-the fear of his son becoming greater than him, he didn’t send him to school. When he was sixteen, his father burnt down the house. This situation created anger in him. As a result the old man killed his father with a knife. The OLD MAN then became a peddler. The old man tells his bastard son that the night is the anniversary of mother’s wedding. As he finishes telling his son about the past, a shadow appears to which the man can only see. The shadow is of his dead mother. 

A little later her husband also appears, and they both proceed towards room. The old man objects to the way they go inside. After the incident is over the boy talks about property he has acquired. The bastard son demands for his share in property of his father, which is denied by him. It arises anger in him. As a result he takes moneybag from the Old man. A quarrel starts between them; the boy gets killed at last with the knife of the old man. The old man, after it, addresses his mother and claims that he has ended the consequences. He hopes that the soul of mother would be purified.