Abdullah bin Abbas reported,

Sad is not among the obligatory prostrations, but I saw the Prophet ﷺ prostrate during it.

Bukhari 3422

Sahih

حدثنا موسى بن إسماعيل حدثنا وهيب حدثنا أيوب عن عكرمة

عن ابن عباس رضي الله عنهما قال

ليس ص من عزائم السجود ورأيت النبي ﷺ يسجد فيها

البخاري 3422صحيح
Contents
Reference
Commentary
Ayat
Collection
Sahih Bukhari
Book
Hadiths of the prophets
Chapter
And remember Our servant Dawud, the possessor of strength; indeed, he was one who repeatedly turned back to Allah" to His saying, "and discernment in speech
Numbering
Darussalam 3422
Bukhari 3422