Anyone who has seen this phenomenon will have had their stomach turned by it. The remarkable fact about the dog that returns to eat its own vomit is that it overcomes the nausea that induced it to vomit in the first place.
How can this terrible cycle be broken? Not without the help of God and with prayer. Let a man become disgusted with his sin and ask God to convict him of it and show him its depravity. Let him long to see the world as God sees it and be free from the delusion that sees sin as profitable or desirable. Let him acknowledge his fallen nature and long to be free from it. Let him mourn the weakness that has made him return to it again and again, and suppress the voice of conscience to his own hurt and shame. Let him cry out to God for forgiveness and for a new nature that will release him from bondage to foolishness, and allow him to say with conviction that foolishness is indeed foolishness.