即以其人之道，还治其人之身

jí yǐ qí rén zhī dào, huán zhì qí rén zhī shēn

[do unto them as they do unto us; answer a fool according to his folly; deal with sb. as he deals with you; does sb. with his own physique; give sb. a dose of his own medicine; pay sb. back in his own coin; requite like for like; pay back in kind] 就拿这个人整治他人的方式, 反过来整治这个人本身