(93) باب الاِلْتِفَاتِ فِي الصَّلاَةِ
Narrated `Aisha:
I asked Allah's Messenger (ﷺ) about looking hither and thither in prayer. He replied, "It is a way of stealing by which Satan takes away (a portion) from the prayer of a person."
Reference: Sahih al-Bukhari 751
In-book reference: Book 10, Hadith 145
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 1, Book 12, Hadith 718