عَنِ النُّعْمَانِ بْنِ بَشِيرٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «الدُّعَاءُ هُوَ الْعِبَادَةُ» ثُمَّ قَرَأَ: (وَقَالَ رَبُّكُمُ ادْعُونِي أَسْتَجِبْ لَكم) رَوَاهُ أَحْمَدُ وَالتِّرْمِذِيُّ وَأَبُو دَاوُدَ وَالنَّسَائِيُّ وَابْنُ مَاجَه

He reported God’s messenger as saying, “Supplicate God when you are assured of being answered, and know that God does not answer a supplication which comes from a careless and inattentive heart.”Tirmidhi transmitted it, saying this is a gharib tradition.