Does Allah answer the prayers of a sinner, and is there any indication that Iblis's supplication to his Lord was answered?

It is incorrect to say that the prayer of a sinner is not answered. Sins may be one of the impediments to the answering of prayers, but this does not mean that all the prayers of a sinner are rejected. Good deeds or sincere supplication may nullify the effect of sin. Ibn Rajab mentioned that excessive indulgence in unlawful things and consuming them are impediments to the answering of prayers, as is neglecting obligatory duties such as enjoining good and forbidding evil.

Scholars differed regarding the answering of Iblis's prayer for respite. Some said that it was an answer and used it as evidence that the prayer of a disbeliever may be answered, and that it might be a gradual enticement (istidraj), as Al-Alusi stated. Others held that it was a notification of Allah's eternal decree and not an answer to his prayer.

Based on the view that Iblis's prayer was answered, some scholars understood this to encourage the Muslim to supplicate and not despair of an answer, even if they are a sinner and fall short, for Allah Almighty answered Iblis, who is the worst of creation.