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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bukhari:2448 – Yaḥyá b. Mūsá > Wakīʿ > Zakariyyāʾ b. Isḥāq al-Makkī > Yaḥyá

The Prophet ﷺ sent Muʿadh to Yemen and said, "Be afraid, from the curse of the oppressed as there is no screen between his invocation and Allah."  

البخاري:٢٤٤٨ – حَدَّثَنَا يَحْيَى بْنُ مُوسَى حَدَّثَنَا وَكِيعٌ حَدَّثَنَا زَكَرِيَّاءُ بْنُ إِسْحَاقَ الْمَكِّيُّ عَنْ يَحْيَى بْنِ عَبْدِ اللَّهِ بْنِ صَيْفِيٍّ عَنْ أَبِي مَعْبَدٍ مَوْلَى ابْنِ عَبَّاسٍ عَنِ ابْنِ عَبَّاسٍ ؓ

أَنَّ النَّبِيَّ ﷺ بَعَثَ مُعَاذًا إِلَى الْيَمَنِ فَقَالَ: «اتَّقِ دَعْوَةَ الْمَظْلُومِ، فَإِنَّهَا لَيْسَ بَيْنَهَا وَبَيْنَ اللَّهِ حِجَابٌ۔»  

See similar narrations below:

Collected by Tirmidhī, Suyūṭī
tirmidhi:2014 – Abū Kurayb > Wakīʿ > Zakariyyā b. Isḥāq

"The Messenger of Allah sent Mu'adh [bin Jabal] to Yemen, and said: 'Beware of the supplication of the oppressed; for indeed there is no barrier between it and Allah.'"  

الترمذي:٢٠١٤ – حَدَّثَنَا أَبُو كُرَيْبٍ حَدَّثَنَا وَكِيعٌ عَنْ زَكَرِيَّا بْنِ إِسْحَاقَ عَنْ يَحْيَى بْنِ عَبْدِ اللَّهِ بْنِ صَيْفِيٍّ عَنْ أَبِي مَعْبَدٍ عَنِ ابْنِ عَبَّاسٍ

أَنَّ رَسُولَ اللَّهِ ﷺ بَعَثَ مُعَاذَ بْنَ جَبَلٍ إِلَى الْيَمَنِ فَقَالَ اتَّقِ دَعْوَةَ الْمَظْلُومِ فَإِنَّهَا لَيْسَ بَيْنَهَا وَبَيْنَ اللَّهِ حِجَابٌ  

قَالَ أَبُو عِيسَى وَفِي الْبَابِ عَنْ أَنَسٍ وَأَبِي هُرَيْرَةَ وَعَبْدِ اللَّهِ بْنِ عُمَرَ وَأَبِي سَعِيدٍ وَهَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ وَأَبُو مَعْبَدٍ اسْمُهُ نَافِذٌ
suyuti:407a –

The Prophet ﷺ sent Muʿadh to Yemen and said, "Be afraid, from the curse of the oppressed as there is no screen between his invocation and Allah." (Using translation from Bukhārī 2448)   

السيوطي:٤٠٧a –

"اتَّقِ دعوة المظلومِ فإنه ليس بينها وبين الله حجابٌ".  

[خ] البخاري [م] مسلم عن معاذ بن جبل