This article analyzes a single withcraft case that was investigated in the Grand Duchy of Lithuania. That case appears on the surface to have been typical of the majority of surviving trials. It was a rural trial that reflected the tensions and conflicts in peasant society and did not exhibit any features of learned demonology. Both the accused and accusers came from the same social status (the status was not even specified in the case), the exception being one of the defendants who was the wife of a minor official. The case is, nevertheless, unusual and idiosyncratic in terms of both the accusation against the defendants and the procedure employed to decide their fate. The suspected witches were charged with spoiling the harvest, a charge that was fairly rarely voiced in the witchcraft trials of the Grand Duchy, and were subjected to ordeal by water. In order to understand the logic behind the implementation of the ordeal, the essay draws upon materials from Westphalia and Ancient Rus' in addition to those stemming solely from the Grand Duchy of Lithuania.