Lu Ban (魯班) was supposed to be a consummate carpenter in ancient times.
It is said that he once carved a wooden phoenix that was so lifelike that it actually flew in the sky for three days.
Thus it was considered the height of folly to show off one's skill with an axe in front of Lu Ban.
班門弄斧
古代有一個建筑和雕刻技術非常高超的人，名叫魯班。
傳說他曾用木頭制作了一只五彩斑斕的鳳凰，能夠在空中飛翔三天不掉下來。
誰敢在魯班門前賣弄使用斧子的技術，也就是說，想在大行家面前顯示自的本領，這種太不謙虛的可笑行為，就叫做“班門弄斧”（ 這句成語有時也用作自謙之詞，表示自己不敢在行家面前賣弄自己的小本領）。
It is said that he once carved a wooden phoenix that was so lifelike that it actually flew in the sky for three days.
Thus it was considered the height of folly to show off one's skill with an axe in front of Lu Ban.
班門弄斧
古代有一個建筑和雕刻技術非常高超的人，名叫魯班。
傳說他曾用木頭制作了一只五彩斑斕的鳳凰，能夠在空中飛翔三天不掉下來。
誰敢在魯班門前賣弄使用斧子的技術，也就是說，想在大行家面前顯示自的本領，這種太不謙虛的可笑行為，就叫做“班門弄斧”（ 這句成語有時也用作自謙之詞，表示自己不敢在行家面前賣弄自己的小本領）。