Sahih Muslim 6929

حَدَّثَنَا إِسْحَقُ بْنُ إِبْرَاهِيمَ أَخْبَرَنَا عِيسَى بْنُ يُونُسَ حَدَّثَنَا عَبْدُ الْمَلِكِ بْنُ أَبِي سُلَيْمَانَ عَنْ أَبِي الزُّبَيْرِ عَنْ صَفْوَانَ وَهُوَ ابْنُ عَبْدِ اللَّهِ بْنِ صَفْوَانَ وَكَانَتْ تَحْتَهُ الدَّرْدَاءُ قَالَ قَدِمْتُ الشَّامَ فَأَتَيْتُ أَبَا الدَّرْدَاءِ فِي مَنْزِلِهِ فَلَمْ أَجِدْهُ وَوَجَدْتُ أُمَّ الدَّرْدَاءِ فَقَالَتْ أَتُرِيدُ الْحَجَّ الْعَامَ فَقُلْتُ نَعَمْ قَالَتْ فَادْعُ اللَّهَ لَنَا بِخَيْرٍ فَإِنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ كَانَ يَقُولُ دَعْوَةُ الْمَرْءِ الْمُسْلِمِ لِأَخِيهِ بِظَهْرِ الْغَيْبِ مُسْتَجَابَةٌ عِنْدَ رَأْسِهِ مَلَكٌ مُوَكَّلٌ كُلَّمَا دَعَا لِأَخِيهِ بِخَيْرٍ قَالَ الْمَلَكُ الْمُوَكَّلُ بِهِ آمِينَ وَلَكَ بِمِثْلٍ

Safwan (and he was Ibn 'Abdullah b. Safwan, and he had been married to Umm Darda') reported: I visited Abu Darda's house in Syria. I did not find him there but Umm Darda' (was present at the house). She said: Do you intend to perform Hajj during this year? I said: Yes. She said: Do supplicate Allah for blessings upon us, for Allah's Apostle (may peace be upon hiin) used to say: The supplication of a Muslim for his brother at his back (in his absence) is responded so long as he makes a supplica- tion for blessings for his brother and the commissioned Angel says: Amen, and says: May it be for you too I I went to the bazar and met Abfi Dardi' and he narrated like this from Allah's Messenger ( ‌صلی ‌اللہ ‌علیہ ‌وسلم ‌ ).