You have asked a rather broad question. I suppose the main characteristic of this excellent story is the way that it operates as an allegory. Let us remember that an allegory is a story that operates on two different levels--the literal and the symbolic. What happens in an allegorical tale and the characters that populate such a story can be understood both literally and symbolically. As we read this story, it is clear that there is an obvious allegorical reading to this tale of how one man is conquered by the devil by his own greed. It is possible to argue that Pahom could stand for the human soul, and the devil for human weakness. The Commune, where Pahom starts off his life, stands for sharing and empathy, whereas the private land that Pahom wants more of insatiably represents greed and lack of empathy. Lastly, we could argue that Pahom's trip to the land of the Bashkirs could stand for the way that his greed for land has distanced him from sound values, and his final death could stand for his moral degeneration.
Through the entire story therefore, we see that each character and action has allegorical significance, which supports the theme of the story: unchecked ambition and greed destroy people. The death of Pahom demonstrates the harm of striving too much for material gain. Note how the irony of the ending supports this:
His servant picked up the spade and dug a grave long enough for Pahom to lie in, and buried him in it. Six feet from his head to his heels was all he needed.
Thus it is that in spite of Pahom's insatiable desire for ever-more land, at the end of the story the question in the title is answers. Six feet is all a man needs.