Abu Sirmah (RAA) narrated that the Messenger of Allah (ﷺ) said:
"He who causes harm to a Muslim will be harmed by Allah, and he who acts in a hostile manner against a Muslim, will be punished in the same way by Allah." Related by Abu Dawud and At-Tirmidhi who graded it to be Hasan (good). (DE)
English reference (DE): Book 16, Hadith 1544 (DE)
Arabic reference (DE): Book 16, Hadith 1501 (DE)