Malik related to me from Ishaq ibn Abdullah ibn Abi Talha that Anas ibn Malik said, "I heard Umar ibn al-Khattab, when I was going out with him to visit an orchard, say to himself, and there was a wall between him and me and he was inside the garden, 'Umar ibn al-Khattab, amir al-muminin! Well done! Well done! By Allah, fear Allah or he will punish you.' "  

قَالَ سَمِعْتُ عُمَرَ بْنَ الْخَطَّابِ وَخَرَجْتُ مَعَهُ حَتَّى دَخَلَ حَائِطًا فَسَمِعْتُهُ وَهُوَ يَقُولُ وَبَيْنِي وَبَيْنَهُ جِدَارٌ وَهُوَ فِي جَوْفِ الْحَائِطِ عُمَرُ بْنُ الْخَطَّابِ أَمِيرُ الْمُؤْمِنِينَ بَخٍ بَخٍ وَاللَّهِ لَتَتَّقِيَنَّ اللَّهَ أَوْ لَيُعَذِّبَنَّكَ  

[Machine] I once heard Umar ibn al-Khattab say, as I was walking with him until we reached a wall, and I heard him say while he was inside the wall, "Umar, the Commander of the Believers, be cautious, by Allah, O son of al-Khattab, that you fear Allah and obey Him, or else He will torment you."  

سَمِعْتُ عُمَرَ بْنَ الْخَطَّابِ يَوْمًا وَخَرَجْتُ مَعَهُ حَتَّى دَخَلَ حَائِطًا فَسَمِعْتُهُ وَهُوَ يَقُولُ وَبَيْنِي وَبَيْنَهُ جِدَارٌ وَهُوَ فِي جَوْفِ الْحَائِطِ «عُمَرُ أَمِيرَ الْمُؤْمِنِينَ بَخٍ بَخٍ وَاللَّهِ بَنِي الْخَطَّابِ لَتَتَّقِيَنَّ اللَّهَ أَوْ لَيُعَذِّبَنَّكَ»