To cover one's ears while stealing a bell
To deceive oneself and others; to aim to conceal something that cannot be concealed
Negative
一个人做了坏事，还编出一套理由来掩饰，那就是掩耳盗铃，自欺欺人 | Yīgè rén zuò le huàishì, hái biān chū yī tào lǐyóu lái yǎnshì, nà jiùshì yǎn'ěrdàolíng, zìqīqīrén
When a person does something bad and then fabricates an excuse, that's just them lying to themselves and to others
[Source]
事情已经清楚了，你还想掩耳盗铃？ | Shìqíng yǐjīng qīngchǔ le, nǐ hái xiǎng yǎn'ěrdàolíng?
Everything has already been cleared up, but you still want to try and hide things?
[Source]
None
掩耳盗钟 (yàn ěr dào zhōng)
So, in ancient times, if someone committed a serious crime, they and their entire family (wives, children, etc) could be executed. I'm not entirely sure what crime was committed here, but know at least that slaughtering an entire family was a thing. (Obviously this is a very scholarly explanation — if someone does actually know more about this, please let me know!)
《吕氏春秋》(Lǚ Shì Chūn Qiū), a compilation of the philosophies of the Hundred Schools of Thought. It was created during the Qín Dynasty (秦, 221 - 207 BC) with the patronage of Chancellor 吕不韦 (Lǚ Bù Wéi)
During the Spring and Autumn Period (春秋时期, chūn qiú shí qī, 770 - 476 BC), a powerful aristocratic family had another family executed. One thief realized that the now-deceased family's household would be unoccupied and its riches therefore unprotected, and he rushed over immediately.
When he managed to get into the courtyard, he was delighted to discover an exquisitely-crafted bronze bell. He tried to hoist it onto his back and carry it away, but the bell dwarfed him in in size, and his efforts quickly failed.
However, this initial failure didn't deter him. After some thought, the thief decided that he would break the bell into pieces and transport it that way. He went and found a hammer, then slammed it against the bell with all his might. Immediately, a deafening clang rang through the air.
The thief started violently, and he began to get extremely nervous. Such a loud ringing would certainly alert others that he was here, and he didn't want to get caught, so he needed to come up with a way to silence the noise immediately. After some more thought, he slammed his hands against his ears. The ringing of the bell stopped immediately, and he let out a sigh of relief.