ㄧㄤˇㄩㄥˊㄏㄨㄢˋyǎngyōng‑yíhuàn

养痈遗患
  1. 不及治療以致留下禍害比喻寬容壞人壞事留下禍根養癰成患」。 趁早打擊黑社會集團必然養癰遺患」。

lit. to foster an ulcer and bequeath a calamity (idiom)​; tolerating budding evil can only lead to disaster, to cherish a viper in one's bosom