Jami` at-Tirmidhi 2303
جامع الترمذي#2303SahihClarification of this is in the Hadith of 'Umar bin Al-Khattab, from the Prophet(s.a.w) who said:"The best of people are my generation, then those who follow them,then those who follow them. Then lying will spread, until a man testifies while his testimony was not requested, and a man will take an oath while an oath was not sought
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Zubair Ali ZaiSahih
In-book reference: 35:10