The Messenger of Allah ﷺ said, "Whatever two people say when they revile each other falls on the one who started it, unless the wronged party exceeds the bounds."
Azami 14946
Sahih
عن أبي هريرة
أن رسول الله ﷺ قال: المستبان ما قالا، فعلى البادئ ما لم يعتد المظلوم.
Muslim narrated it in Birr and Silah (2587) through multiple routes from Ismail bin Jafar, from Ala, from his father, from Abu Hurairah, who mentioned it.