كتاب الصلاة
2  
The Book of Prayer
Bulugh al-Maram 248
Narrated Jabir bin Samura (RA):
Allah's Messenger (ﷺ) said: "Those people who raise their eyes to heaven while in Salat (prayer) should stop (doing so) or else their sight will not return to them." [Reported by Muslim].
وَعَنْ جَابِرِ بْنِ سَمُرَةٍ ‏- رضى الله عنه ‏- قَالَ : قَالَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-{ لَيَنْتَهِيَنَّ قَوْمٌ يَرْفَعُونَ أَبْصَارَهُمْ إِلَى اَلسَّمَاءِ فِي اَلصَّلَاةِ أَوْ لَا تَرْجِعَ إِلَيْهِمْ } رَوَاهُ مُسْلِمٌ .‏ 1
Reference : Bulugh al-Maram 248
In-book reference : Book 2, Hadith 248
English translation : Book 2, Hadith 246
Hadith Text
Reference