What does Proverbs 28:9 mean?

One of the more common versions of false faith is the attempt to use God as a vending machine, or a genie. His laws and commands are ignored, but He is still expected to cooperate with prayer requests. God despises this attitude, both when attached to prayer and to sacrifice (Proverbs 15:8). Notably, the Bible says God feels revulsion towards that entire "way" of being, not merely to certain moments (Proverbs 15:9). The term used for His reaction comes from the Hebrew tow'ēbah, which implies deep disgust and loathing. When someone has no concern for God's will, or obedience, or repentance, their attempts to "play religious" are met with the equivalent of divine nausea. Even a "good deed" is a sin when it's done out of insincere motives.

Of course, God has the right to respond to anyone's prayer in any way He chooses. He may respond to an appeal from a non-believer as a means of calling them to faith. Yet those who reject God have no valid reason to expect positive answers to their prayers. Scripture makes it clear that sin and disbelief are barriers to His cooperation. The psalmist understood that sin erects a barrier between prayer and a positive response from God. He writes in Psalm 66:18: "If I had cherished iniquity in my heart, the Lord would not have listened." The man born blind who was healed by Jesus told the Pharisees, "We know that God does not listen to sinners" (John 9:31).

Jesus often denounced the Pharisees because of their hypocrisy. He told the story of a Pharisee and a tax collector who entered the temple to pray. The tax collector who humbly admitted he was a sinner and asked God to be merciful to him went home justified. The self-righteous Pharisee who saw others as sinful but himself as righteous did not (Luke 18:9–14).