当dāng仁rén不bù让ràng

Literal: facing benevolence, not yielding
Figurative: To take on, without false modesty, what is rightly yours or what you are best suited for; unlike 毛遂自荐, it is not about volunteering unasked.

Where does 当仁不让 come from?

There is no anecdote behind it, but a saying of Confucius recorded in the Analects, in the chapter "Wei Ling Gong": when it comes to benevolence, do not give way even to your teacher. In other words, when the matter is acting with benevolence (仁, ren), the deference owed to one's teacher is no excuse for hanging back. The idiom grew out of that line and over time lost much of its moral tone: today it describes someone who takes on, without fuss, what falls to them or what they are best suited for, and also a favorite who wins what everyone expected them to win.

Source (出处): 《论语·卫灵公》

How is 当仁不让 used? Two examples

红hóng烧shāo肉ròu是shì他tā的de拿ná手shǒu菜cài，今jīn天tiān掌zhǎng勺sháo的de活huó儿r他tā当dāng仁rén不bù让ràng。
Braised pork is his signature dish, so naturally he's the one taking charge of the stove today.
大dà家jiā都dōu推tuī你nǐ当dāng队duì长zhǎng，论lùn能néng力lì也yě数shǔ你nǐ最zuì强qiáng，你nǐ就jiù当dāng仁rén不bù让ràng吧ba。
Everyone wants you as captain, and you're the most capable of us, so step up and take it.

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