How does Wiesel alter the animal imagery in the description of Eliezer’s beating? Explain the purpose behind the change in images.

In his description, Wiesel alternates the imagery, using Idek as the animal rather then Elie,

He leapt on me, like a wild animal, hitting me on the chest ,on the head.....

Wiesel does this to juxtapose the vision of a violent animal (Idek) with the helpless animal (Jews).