Mishkat al-Masabih
Prayer — Hadith #881
وَعَنْ عَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ قَالَ: خَرَجَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ حَتَّى دَخَلَ نَخْلًا فَسَجَدَ فَأَطَالَ السُّجُودَ حَتَّى خَشِيتُ أَنْ يَكُونَ اللَّهُ تَعَالَى قَدْ تَوَفَّاهُ. قَالَ: فَجِئْتُ أَنْظُرُ فَرَفَعَ رَأْسَهُ فَقَالَ: «مَا لَكَ؟» فَذَكَرْتُ لَهُ ذَلِكَ. قَالَ: فَقَالَ:
" إِنَّ جِبْرِيلَ عَلَيْهِ السَّلَام قَالَ لي: أَلا أُبَشِّرك أَن اللَّهَ عَزَّ وَجَلَّ يَقُولُ لَكَ مَنْ صَلَّى عَلَيْكَ صَلَاةً صَلَّيْتُ عَلَيْهِ وَمَنْ سَلَّمَ عَلَيْكَ سلمت عَلَيْهِ ". رَوَاهُ أَحْمد
God’s Messenger went out and entering among some palm trees prostrated himself so long that I was afraid God had taken his soul. I went and looked, and he raised his head and said, “What is the matter with you? I mentioned that to him, and he told me that Gabriel had come and given him the good news that God said, “If anyone invokes one blessing on you I will bless him, and if anyone greets you I will greet him.”
Ahmad transmitted it.