(10) باب إِذَا قَالَ أَشْهَدُ بِاللَّهِ، أَوْ شَهِدْتُ بِاللَّهِ
Narrated `Abdullah:
The Prophet (ﷺ) was asked, "Who are the best people?" He replied: The people of my generation, and then those who will follow (come after) them, and then those who will come after the later; after that there will come some people whose witness will precede their oaths and their oaths will go ahead of their witness." Ibrahim (a sub-narrator) said, "When we were young, our elder friends used to prohibit us from taking oaths by saying, 'I bear witness swearing by Allah, or by Allah's Covenant."'
Reference: Sahih al-Bukhari 6658
In-book reference: Book 83, Hadith 37
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 8, Book 78, Hadith 652