تقوا دعوة المظلوم وإن كان كافرا فإنه ليس دونها حجاب» .
(حسن) … [حم, ع, الضياء] عن أنس. الصحيحة 767)
It is reported that the Messenger of Allah, peace and blessings of Allah be upon him, said:
“Fear the oppressed’s supplications, even if he is a disbeliever , for there is no barrier in front of it (which will prevent it from being accepted)!” .
This hadith was transmitted by Ahmad (3/153), Abu Ya’lya (1337), ad-Diya al-Makadisi in al-Muhtara (2748) according to Anas, may Allah be pleased with him.
Sheikh al-Albani called the hadith good. See “Sahih al-Jami ‘al-sagir” (119), “al-Silsil al-sahih” (767).
Imam al-Munawi said: “This means: beware of injustice, so that the oppressed’s curse does not invoke you, even if he is an infidel or a sinner, because the oppressed’s prayer receives an answer, while his wickedness remains with him.” See Faydul Kadir (1/236).