(26) باب أَيَّامِ الْجَاهِلِيَّةِ
Narrated Ibn `Umar:
The Prophet (ﷺ) said, "If anybody has to take an oath, he should swear only by Allah." The people of Quraish used to swear by their fathers, but the Prophet (ﷺ) said, "Do not swear by your fathers. "
Reference: Sahih al-Bukhari 3836
In-book reference: Book 63, Hadith 62
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 5, Book 58, Hadith 177