IF YOU ARE A NON-BELIEVER (someone who maybe "believes" but continues knowingly and purposely in their sinful ways, hasn't repented, etc.) -
John 9:31 declares, “We know that God does not hear sinners, but those who worship Him and do His will, those He hears.” It has also been said that "the only prayer that God hears from a sinner is the prayer for salvation." As a result of this Scripture, some believe that God does not hear and/or will never answer the prayers of an unbeliever. In context, though, the Scripture is saying that God does not perform miracles through an unbeliever. The following Scriptures describe God hearing and answering the prayers of an unbeliever. 1 John 5:14-15 tells us that God answers prayers based on whether they are asked according to His will. This principle, perhaps, applies to unbelievers. If an unbeliever asks a prayer of God that is according to His will, nothing prevents God from answering such a prayer – according to His will.
In examining the following passages, in most of these cases prayer was involved. In one or two, God responded to the cry of the heart (it is not stated whether that cry was directed toward God). In some of these cases, the prayer seems to be combined with repentance. But in other cases, the prayer was simply for an earthly need or blessing, and God responded either out of compassion or in response to the genuine seeking or faith of the person. Here are some passages dealing with prayer by an unbeliever:
The people of Ninevah; Jonah 3:5-10; that Ninevah might be spared.
Hagar and Ishmael; Genesis 21:14-19; not so much a prayer as a cry of the heart concerning her son who was close to death.
Ahab; 1 Kings 21:17-29; esp. v. 27-29; Ahab fasts and mourns over Elijah's prophecy concerning his posterity. God responds by not bringing about the calamity in Ahab's time.
The woman from the Tyre and Sidon area; Mark 7:24-30; that Jesus would deliver her daughter from a demon.
Cornelius, the Roman centurion; Acts 10; the prayer request is not stated (Acts 10:30), but he is shown the way of salvation.
God does make promises that are applicable for all (saved and unsaved alike) such as Jeremiah 29:13: "And ye shall seek me, and find me, when ye shall search for me with all your heart." This was the case for Cornelius in Acts 10:1-6. But there are many promises that, according to the context of the passages, are for Christians alone. Because Christians have received Christ, we are encouraged to come boldly unto the throne of grace to find help in time of need (Hebrews 4:14-16). We are told that when we ask for anything according to God's will, He hears and gives us what we ask for (1 John 5:14-15). There are many other promises for Christians concerning prayer as well (Matthew 21:22; John 14:13; John 15:7). So, yes, there are instances in which God does not answer the prayers of an unbeliever. At the same time, in His grace and mercy, God can intervene in the lives of unbelievers in response to their prayers.
http://www.christianbook.com/Christian/Books/product?event=AFF&p=1011693&item_no=52182X
