Riyad as-Saliheen 1561
Abu Hurairah (May Allah be pleased with him) said:
The Messenger of Allah ﷺ said, "When two persons indulge in abusing each other, the beginner will be the sinner so long as the oppressed does not transgress the limits."
[Muslim].
وعن أبي هريرة رضي الله عنه أن رسول الله ﷺ قال:
"المتسابان ما قالا فعلى البادي منهما حتى يعتدي المظلوم" ((رواه مسلم)).
Classification
Sahih (Authentic)
References
Riyad as-Saliheen 1561
Riyad as-Saliheen Book of Prohibited actions, Hadith 51