Stealing ear bells: it turned out to be stealing ear bells. Cover: cover; Steal: steal. Stealing the bell, thinking that if you can't hear others, you can't hear them, which is a metaphor for deceiving yourself.

Source: Lu's "Spring and Autumn Self-knowledge": "Fan died and the people got a clock. If they want to leave, the bell is too loud to be negative; If the spine is damaged, the bell will ring. If you are afraid that people will smell it and catch you, cover their ears. The wicked can smell it; If you are evil, you will hear it yourself. "