Apparently He makes the decision to "not" hear some prayers. It is the same as when He turned from the crucifixion of His Son, prompting the statement of "why hast thou forsaken me". There are some things in which God will not take part; the word describes Him as turning His face. Today we would say we hid our eyes from something. Back to the original topic, the text provided makes it clear that God does not entertain the prayers/petitions of sinners.
For the eyes of the Lord are over the righteous, and his ears are open unto their prayers: but the face of the Lord is against them that do evil.
1 Peter 3:12
Now we know that God heareth not sinners: but if any man be a worshipper of God, and doeth his will, him he heareth.
John 9:31
If we are a worshipper of God, and doeth His will, He hears us. Being a worshipper is equivalent to saying we have faith in God and if we love Him we will do His will or obey His commandments.
Blessed are they that do his commandments, that they may have right to the tree of life, and may enter in through the gates into the city.
Rev 22:14
And hereby we do know that we know him, if we keep his commandments.He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.
1 John 2:4
We must obey God before we enter into a relationship with Him. Once we obey Him we enter into His grace....if we stop attempting to live the life Christ would have us live, we then fall from His grace.
But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.
1 John 1:7
In Him