Help with a proverb

Hello r/Dutch! I came across the proverb "No one looks for others in the oven who has not been in there himself" in the Wikipedia article for the painting Netherlandish Proverbs by Pieter Bruegel the Elder. Wikipedia says it means "To imagine wickedness in others is a sign of wickedness in oneself" which I (sort of) understand, but what I'm stuck on is... why is someone in the oven? Is this a cheating wife hides her lover in the closet when her husband gets back from work early situation? Hansel and Gretel? Is Wikipedia wrong about what it means? Help!