Hadith: What is the matter with some people who raise their eyes towards the sky during their prayer?" He went on, using strict words, until he said, "They must stop that, or their eyesight will be snatched away

عَن أَنَسِ بْنِ مَالِكٍ رضي الله عنه قَالَ: قَالَ النَّبِيُّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ:
«مَا بَالُ أَقْوَامٍ يَرْفَعُونَ أَبْصَارَهُمْ إِلَى السَّمَاءِ فِي صَلاَتِهِمْ»، فَاشْتَدَّ قَوْلُهُ فِي ذَلِكَ، حَتَّى قَالَ: «لَيَنْتَهُنَّ عَنْ ذَلِكَ أَوْ لَتُخْطَفَنَّ أَبْصَارُهُمْ».
[صحيح] - [رواه البخاري] - [صحيح البخاري: 750]

Anas ibn Mālik (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) said:
"What is the matter with some people who raise their eyes towards the sky during their prayer?" He went on, using strict words, until he said, "They must stop that, or their eyesight will be snatched away."
[Authentic hadith] - [Narrated by Bukhari] - [Sahih Bukhari - 750]

Explanation

The Prophet (may Allah's peace and blessings be upon him) warned those who raise their eyes to the sky during prayer, whether during supplication or other times. His rebuke became more severe, and he (may Allah's peace and blessings be upon him) threatened that those who do so might have their eyesight snatched away swiftly, to the point that they would not even realize it until they had lost the blessing of sight.

Benefits from the Hadith

1. The excellence of the Prophet's approach in making Da‘wah and his clarification of the truth, as he did not expose the person who was in error since the goal was to clarify the truth, which had been achieved, and because he concealed the one upon error and made the message more likely to be accepted.
2. A firm prohibition and a stern warning for those who raise their sights to the sky during prayer.
3. In ‘Awn Al-Ma‘būd, he said: The reason for this is that raising one’s eyes to the sky distracts him from the proper direction of the Qiblah, causing one to turn away from it and from the correct posture of the prayer.
4. Raising the eyes contradicts the humility and focus required in prayer.
5. The great significance of prayer, and that the one praying must observe complete reverence and proper conduct with Allah Almighty.