《礼记·文王世子》
听人说： 作臣子的，如果牺牲自己但却能为国君带来好处，这样的事就值得做。 
闻之曰：为人臣者，杀其身有益于君则为之，况于其身以善其君乎？
I have heard it said that if a minister can sacrifice himself but benefit the monarch, then this is something that is worth doing.