what does elie witness Idek doing? consequentially, what is Idek's punishment for him ?

Elie witnesses Idek having sex with a prisoner. Knowing that Idek moved all the prisoners to a different building for this specific reason, Eliezer bursts out laughing. Later, he receives twenty-five strokes of the whip from Idek in front of everyone. Eliezer faints, loses control of his muscles, and is threatened by Idek never to tell anyone what he saw.