In an episode of Person of Interest, an American sci-fi crime drama, a detective is directed by his superior to turn in his badge and service gun. When asked by his partner what it is all about, he replies, “Just chickens coming home to roost.” How does the investigation of an allegedly dirty cop have anything to do with chickens?

“Chickens come home to roost” is a proverbial expression meaning that one’s past wrongdoings will eventually rebound on oneself. According to The American Heritage Dictionary of Idioms, the fact that farm chickens go out to forage during the day and return, by night, to the safety of their henhouse to roost, has long been common knowledge. But it was not until 1809, when Robert Southey wrote, “Curses are like young chickens, they always come home to roost” (The Curse of Kehama), that the idea was figuratively used. It is easy to find its abbreviated versions from then on, such as “the debt chickens come home to roost as the immediate crisis recedes” (The New Daily, 13 April 2020).

Unlike the saying “reap the harvest” which may refer to both positive and negative consequences, “chickens come home to roost” is often connected with undesirable impacts arising from past misdeeds or indiscretions. So, if you are trying to reassure a friend that what he did will bear positive fruit, you may want to leave homing chickens out of the conversation.

在日本电影《检察狂人》中，木村拓哉饰演的检察官眼见杀害青梅竹马的凶手因诉讼时效已过而逍遥法外，心有不甘，选择做扑火飞蛾，为求伸张公义，不惜以身试法。面对后辈质问，他冷然道：“为了顽强地生存下去，只能执着于自己的正义。”对自诩替天行道的人而言，让恶人“自食其果”不能等老天，只能靠自己。

“自食其果”这个成语与佛教因果观密不可分。佛教《正法念处经》有偈云：“自业自得果，众生皆如是。”佛教主张种善因得善果，种恶因得恶果；待因缘成熟后，必会有所报，只是不一定在今世发生。果报随善恶业有好有坏，但成语“自食其果”单指恶果，形容自己做坏事，自己受害。

人力时有穷尽，天道永远昭昭，如果人们对此深信不疑，会否更能化戾气为祥和？不过，比起为求好报或惧怕受罚的行善或不作恶，更难能可贵的是不为什么的善良。你听说过麦唛小朋友吗？“有人在的时候，麦唛很乖。没有人在的时候，没有人罚，没有人赞，麦唛依然很乖。没有人在身边时都乖，是发自内心，真正的乖。”（《2001麦唛大道理小月历》）