حَدَّثَنِي أَبُو الطَّاهِرِ، أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي مُعَاوِيَةُ، - وَهُوَ ابْنُ صَالِحٍ - عَنْ رَبِيعَةَ بْنِ يَزِيدَ، عَنْ أَبِي إِدْرِيسَ الْخَوْلاَنِيِّ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم أَنَّهُ قَالَ ‏"‏ لاَ يَزَالُ يُسْتَجَابُ لِلْعَبْدِ مَا لَمْ يَدْعُ بِإِثْمٍ أَوْ قَطِيعَةِ رَحِمٍ مَا لَمْ يَسْتَعْجِلْ ‏"‏ ‏.‏ قِيلَ يَا رَسُولَ اللَّهِ مَا الاِسْتِعْجَالُ قَالَ ‏"‏ يَقُولُ قَدْ دَعَوْتُ وَقَدْ دَعَوْتُ فَلَمْ أَرَ يَسْتَجِيبُ لِي فَيَسْتَحْسِرُ عِنْدَ ذَلِكَ وَيَدَعُ الدُّعَاءَ ‏"‏ ‏.‏

Abu Huraira reported Allah's Messenger (PBUH) as saying: The supplication of the servant is granted in case he does not supplicate for sin or for severing the ties of blood, or he does not become impatient. It was said: Allah's Messenger, what does:" If he does not grow impatient" imply? He said: That he should say like this: I supplicated and I supplicated but I did not find it being responded. and theu he becomes frustrated and abandons supplication. Translation Not Available

Book Ref: Sahih Muslim Book 48 Hadith 6595
Web Ref:  Sahih Muslim Book 35 Hadith 2735 c