Hadith on Dua: Prayer of three people are always answered

Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said, “The supplications of three are never turned back: a fasting person until he breaks his fast, a just leader, and the supplication of the oppressed is raised above the clouds by Allah, the gates of heaven open for it and the Lord says: By My might, I will surely help you in due time.

Source: Sunan al-Tirmidhī 3598

Grade: Hasan (fair) according to Ibn Hajar

عَنْ أَبِي هُرَيْرَةَ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ثَلَاثَةٌ لَا تُرَدُّ دَعْوَتُهُمْ الصَّائِمُ حَتَّى يُفْطِرَ وَالْإِمَامُ الْعَادِلُ وَدَعْوَةُ الْمَظْلُومِ يَرْفَعُهَا اللَّهُ فَوْقَ الْغَمَامِ وَيَفْتَحُ لَهَا أَبْوَابَ السَّمَاءِ وَيَقُولُ الرَّبُّ وَعِزَّتِي لَأَنْصُرَنَّكِ وَلَوْ بَعْدَ حِينٍ

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