The Prophet ﷺ said, "On the Day of Resurrection, you will find among the worst of people the one who comes to these with the talk of those, and to those with the talk of these."
حدثنا معاوية قال حدثنا أبو إسحاق عن الأعمش عن أبي صالح
عن النبي ﷺ قال تجد من شرار الناس يوم القيامة الذي يأتي هؤلاء بحديث هؤلاء وهؤلاء بحديث هؤلاء
Its chain of transmission is sahih. It has occurred before at 7337, and it was narrated by Bukhari 8/21 in the book of Manners, in the chapter on what is said about the two-faced person, and by Muslim 4/2011, no. 2526, in the book of Righteousness, in the chapter on the condemnation of the two-faced person.