Sunan Abi Dawud, Hadith 4715

Abu Hurairah reported the Prophet (May peace be upon him) as saying; Our lord gets down every night to the heaven of this world when a third night remains and says : (Is there anyone) who prays to Me so that I may accept his prayer? (Is there anyone) who asks of Me so that I may give him? (Is there anyone) who asks for my forgiveness so that I may forgive him?

حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ، وَعَنْ أَبِي عَبْدِ اللَّهِ الأَغَرِّ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ يَنْزِلُ رَبُّنَا كُلَّ لَيْلَةٍ إِلَى سَمَاءِ الدُّنْيَا حِينَ يَبْقَى ثُلُثُ اللَّيْلِ الآخِرِ فَيَقُولُ مَنْ يَدْعُونِي فَأَسْتَجِيبَ لَهُ مَنْ يَسْأَلُنِي فَأُعْطِيَهُ مَنْ يَسْتَغْفِرُنِي فَأَغْفِرَ لَهُ ‏" ‏ ‏.‏

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also referenced under: Hadith 4733 (DarusSalam)