《後漢書》有篇《楊震傳》，
據記載楊震做官最清廉。
他為人性情很耿直，
有一件小事可見一斑：
有一次楊震途經昌邑縣，
縣令是當年他舉薦。
為報答老師舉薦恩，
縣令王密心盤算：
送點禮物給恩師吧，
要是派人去太顯眼。
王密也知道恩師廉且直，
可沒有表示又心不安。
終決定懷揣黃金十餘斤，
親自送去在夜間。
楊震一見很生氣，
批評他怎麼可以這樣幹！
王密說：“特趁暗夜無人知。”
楊震說：“腳下有地上有天。
再者還有你和我，
天、地、你、我已四知，
你揣金速回莫遲延！
若要再來說服我，
師生之誼今日斷！”
王密至此愧又慚，
揣金辭師生感歎，
佩服老師廉正清，
楊震美名千古傳。
“暮夜懷金”這成語，
比喻人暗中賄賂把蠢事幹。
To Bestow Gold at Midnight
In the history of Later Han Dynasty there was a biography about Yang Zhen。It says that Yang Zhen was an honest and restrained officer，who had a disposition of uprightness，as can be seen from this story。
Once Yang Zhen was passing Changyi County。The magistrate of the county had been promoted by him。In order to pay the credit of his promotion，the magistrate Wang Mi was racking his brains to find a way to have someone send him some presents。
Wang Mi knew very well this blissful teacher was honest and upright，but he would feel upset lest he rewarded him a little。So he decided to bestow on him a lump of gold weighing 5 kilograms，and take it in person in the middle of the night。
Yang Zhen was very angry at the sight of it and gave him a very strong rebuke！Wang Mi said，“At midnight no one knows。”Yang Zhen said，“but the Earth underfoot and Heaven overhead，and what is more，you and me-Earth，Heaven，you and me four persons know the secret。Go back to your place with the gold and don't delay。If you try to make me accept it one more time there will be no teacher and disciple any more！”
Then Wang Mi was ashamed and defaced like a stricken devil。He emotionally bade his teacher goodnight with the gold，admiring his teacher's virtue even more。
Thus the good name of Yang Zhen goes on and on，but the idiom“To Bestow Gold at Midnight”takes the meaning of some sly vicious bribery。