Sunan Abi Dawud, Hadith 3118

Narrated Anas: The Prophet came upon a woman who was weeping for her child. He said to her: Fear Allah and have patience. She said: What have you to do with my calamity ? She was then told that he was the Prophet. She, therefore, came to him. She did not find doorkeepers at his gate. She said: I did not recognize you, Messenger of Allah. He said: Endurance is shown only at a first blow.

حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا عُثْمَانُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، قَالَ أَتَى نَبِيُّ اللَّهِ صلى الله عليه وسلم عَلَى امْرَأَةٍ تَبْكِي عَلَى صَبِيٍّ لَهَا فَقَالَ لَهَا ‏"‏ اتَّقِي اللَّهَ وَاصْبِرِي ‏"‏ ‏.‏ فَقَالَتْ وَمَا تُبَالِي أَنْتَ بِمُصِيبَتِي فَقِيلَ لَهَا هَذَا النَّبِيُّ صلى الله عليه وسلم ‏.‏ فَأَتَتْهُ فَلَمْ تَجِدْ عَلَى بَابِهِ بَوَّابِينَ فَقَالَتْ يَا رَسُولَ اللَّهِ لَمْ أَعْرِفْكَ فَقَالَ ‏"‏ إِنَّمَا الصَّبْرُ عِنْدَ الصَّدْمَةِ الأُولَى ‏"‏ ‏.‏ أَوْ ‏"‏ عِنْدَ أَوَّلِ صَدْمَةٍ ‏"‏ ‏.‏

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also referenced under: Hadith 3124 (DarusSalam)