北宋时期有位州官，为人极其廉洁。一天晚上，从京城送来一封上司的来信。他猜想这必定是朝廷有什么重要指示，立刻让手下点上蜡烛阅读。谁知读了一半，他又命令把官家的蜡烛吹灭，把自家的蜡烛点上，继续往下看。公差很纳闷，难道官家买的蜡烛不及他自己出钱买的亮吗？之后他才明白，那封信有小半是关于他留在京城家属的情景，他认为这是私事，不能点官家的蜡烛。

There was a local magistrate who was extremely incorruptible during the Northern Song Dynasty. One night, he received a letter from his supervisor in the capital.  Guessing it must be some important instructions from the court, he asked the understrapper to light a candle and read it immediately. But halfway through his reading, he ordered to replace the official candle with his own one and continued to read. The understrapper felt confused, “Was the official candle not bright enough as that bought by himself?” Only later did the understrapper know that nearly half of the letter was about the magistrate’s family in the capital, which he considered a private matter and should not take advantage of official candles.