Muwatta Malik, Book 56, Hadith 1837 (In-Book) ⓘ

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.' "

حَدَّثَنِي مَالِكٌ، عَنْ إِسْحَاقَ بْنِ عَبْدِ اللَّهِ بْنِ أَبِي طَلْحَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، 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 ‏.‏