Sincere supplication of a disbeliever may be answered
3-1-2018 | IslamWeb
Question:
Assalaamu alaykum wa rahmatullaahi wa barakaatuhu, Shaykhs. I have heard that a disbeliever's supplication is responded if he supplicates to Allah, the Exalted, alone, without committing Shirk (associating partners with Allah). I also heard that a Muslim's supplication may not be answered due to his sins. And I also heard that the supplication of a Muslim whose income is haram will not be answered.Please help me understand; I know that there is no contradiction in the religion. I am less knowledgable, but I want to know if this is all true. And if it is, then I want to understand whether the case of the disbeliever is exceptional. He is sinful and probably earns haram money, but his supplication is answered if he does not commit Shirk while making that supplication, while the supplication of a Muslim is not answered when he encounters the same problems? May Allah reward you, Shaykhs. Please do not refer me to previous fatwas, unless they contain a full answer to my this specific question. Please, Shaykhs. May Allah reward you.
Answer:
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger.
It is true that the supplications of a disbeliever may be answered if he is sincere and genuinely turns to his Lord. Allah, the Exalted, says (what means): {And when waves come over them like canopies, they supplicate Allah, sincere to Him in religion. But when He delivers them to the land, there are (some) of them who are moderate (in faith). And none rejects Our signs except everyone treacherous and ungrateful.} [Quran 31:32]
It is also true that sins in general, including unlawful earnings, may prevent the Muslim's supplication from being answered. Sin may be a reason for every tribulation and calamity. Allah, the Exalted, says (what means): {And whatever strikes you of disaster - it is for what your hands have earned, but He pardons much.} [Quran 42:30]
"The Prophet, sallallahu ‘alayhi wa sallam, mentioned the man who undertakes a long journey, with his hair disheveled and him covered with dust. He raises his hands to the sky and says, 'O Lord! O Lord!' while his food is from unlawful earnings, his drink is from unlawful earnings, his clothing is from unlawful earnings, and he was nourished by unlawful earnings. How then can his supplication be answered?" [Muslim]
There is no contradiction in what you mentioned. The disbelief of the disbeliever is a much greater sin than his consumption of unlawful earnings; however, Allah answers his supplication for a certain wisdom. Allah, the Exalted, says (what means): {Is He (not best) Who responds to the desperate one when he calls upon Him and removes evil and makes you inheritors of the earth? Is there a deity with Allah? Little do you remember.} [Quran 27:62]
Al-Qurtubi 
said in his interpretation of this verse, "Allah, the Exalted, has guaranteed to answer the distressed when he invokes Him and has informed us of this about Himself. The reason for this is that the turning of the distressed person to Allah originates from sincerity and an aspiration in the heart to Him alone. Sincerity holds a great value to Allah, regardless of whether it came from a believer or a disbeliever, an obedient or an impious person."
It should be noted that although the sins of the Muslim sinner or the one who consumes unlawful earnings prevent his supplications from being answered, this is not necessarily the case all the time. Allah, the Exalted, may answer his supplication if He wills for a given wisdom.
Allah knows best.