Parashas Metzora · Passuk 15:31
Chabad.org — English translation + Rashi
Torah Temima points to Mar Zutra (Bavli; marking of graves).
English: “And you shall separate …” — it was taught: From where is there a scriptural hint for marking graves? Mar Zutra said: “And you shall separate the children of Israel from their impurity.”
Marking graves
Chazal derive from this verse a hint that graves should be marked so that people can keep away from impurity.