How does conflict help develop the theme?
Ulrich is patrolling the narrow stretch of land on his border. This is land that George continues to use as hunting grounds. This quarrel began with a land dispute between their grandfathers. They have essentially inherited the feud from them. What was once a legal matter has now become personal. And the land over which they argue is basically worthless. It doesn't have much game to hunt. So they are fighting over a piece of land simply because their families have fought over it for generations. This conflict is absurd because it is a conflict for the sake of conflict (or for the sake of tradition). They have been taught to hate one another, all for the sake of a useless piece of land:
The feud might, perhaps, have died down or been compromised if the personal ill will of the two men had not stood in the way; as boys they had thirsted for one another’s blood, as men each prayed that misfortune might fall on the other . . .
This conflict develops the theme that hatred breeds more hatred. It takes an act of goodwill to break the cycle. Had one or both of these men stopped to consider how pointless their feud had become, the hatred would have died. Even when they are pinned under the tree, they continue their threats. But finally, Ulrich makes the first effort. It takes one gesture (the offering of the wine, perhaps symbolic of the Last Supper) to break the tradition of hatred.