[Machine] The Prophet ﷺ entered the mosque and they raised their eyes towards the sky in prayer. He said, "You should lower your gazes, or your eyes will not return to you."  

دَخَلَ النَّبِيُّ ﷺ الْمَسْجِدَ وَقَدْ رَفَعُوا أَبْصَارَهُمْ فِي الصَّلَاةِ إِلَى السَّمَاءِ فَقَالَ «لَتَنْتَهُنَّ أَوْ لَا تَرْجِعُ إِلَيْكُمْ أَبْصَارُكُمْ»  

The Messenger of Allah ﷺ said: "What is the matter with people who lift their gaze to the sky when praying?" And he spoke sternly concerning that until he said: "They must stop that or they will certainly lose their eyesight." (Using translation from Nasāʾī 1193)   

عَنِ النَّبِيِّ ﷺ أَنَّهُ قَالَ «مَا بَالُ أَقْوَامٍ يَرْفَعُونَ أَبْصَارَهُمْ إِلَى السَّمَاءِ فِي صَلَاتِهِمْ؟» فَاشْتَدَّ قَوْلُهُ فِي ذَلِكَ حَتَّى قَالَ «لَتَنْتَهُنَّ عَنْ ذَلِكَ أَوْ لَيَخْطَفَنَّ اللَّهُ أَبْصَارَكُمْ»