The Prophet ﷺ said, "What is wrong with those people who look towards the sky during the prayer?" His talk grew stern while delivering this speech and he said, "They should stop (looking towards the sky during the prayer); otherwise their eyesight would be taken away." (Using translation from Bukhārī 750)   

أَنَّ النَّبِيَّ ﷺ قَالَ مَا بَالُ أَقْوَامٍ يَرْفَعُونَ أَبْصَارَهُمْ إِلَى السَّمَاءِ فِي صَلَاتِهِمْ فَاشْتَدَّ قَوْلُهُ فِي ذَلِكَ حَتَّى قَالَ لَيَنْتَهِيَنَّ عَنْ ذَلِكَ أَوْ لَتُخْطَفَنَّ أَبْصَارُهُمْ  

[Machine] The Messenger of Allah ﷺ said, "Certain people should stop raising their gaze to the sky during supplication in prayer, or else their eyes will be snatched away."  

أَنَّ رَسُولَ اللهِ ﷺ قَالَ لَيَنْتَهِيَنَّ أَقْوَامٌ عَنْ رَفْعِهِمْ أَبْصَارَهُمْ عِنْدَ الدُّعَاءِ فِي الصَّلَاةِ إِلَى السَّمَاءِ أَوْ لَتُخْطَفَنَّ أَبْصَارُهُمْ  

[Machine] The Messenger of Allah ﷺ said, "Certain people should stop raising their gazes to the sky during prayer, or else their vision will not return to them."  

قَالَ رَسُولُ اللهِ ﷺ لَيَنْتَهِيَنَّ أَقْوَامٌ يَرْفَعُونَ أَبْصَارَهُمْ إِلَى السَّمَاءِ فِي الصَّلَاةِ أَوْ لَا تَرْجِعُ إِلَيْهِمْ