割雞焉用牛刀

Etymology
From the Analects, Book 17 (《論語·陽貨》):



In this passage, Confucius was joking with his disciple Yan Yan, suggesting that the ritual court music might be a bit over the top, when considering that Wucheng was such a lowly assignment.

Proverb

 * 1) something of a big calibre is not necessary to handle small or minor problems; there is no need to use a sledgehammer to crack a nut