From John Locke's An Essay Concerning Human Understanding, II.xii.35 -
"It seems so established and settled a maxim by the general consent of all mankind, that good, the greater good determines the will...But yet upon a stricter inquiry, I am forced to conclude, that good, the greater good, though apprehended and acknowledged to be so, does not determine the will, until our desire, raised proportionably to it, makes us uneasy in the want of it...
Let a drunkard see, that his health decays, his estate wastes...yet the returns of his uneasiness to miss his companions; the habitual thirst after his cups, at the usual time, drives him to the tavern, though he has in his view the loss of health and plenty, and perhaps the joys of another life...
'Tis not for want to viewing the greater good: for he sees, and acknowledges it...but when the uneasiness to miss his accustomed delight returns, the greater acknolwedged good loses its hold, and the present uneasiness determines the will to its accustomed action..."
This is a profound truth which sheds light on the human spirit, especially in its sinfulness. How often have I recognized the greater good of pursuing and obeying God, yet succumbed to uneasiness and fallen back into the sinful "accustomed delight" in which I had previously been taking part?
I think that the major issues is that the sin is an "accustomed delight." We're used to it, and it gives us pleasure. So, if we don't want to fall back into that sin as a result of pleasure-seeking, we have to find a new source of pleasure, a new "delight." If Christ is not our delight, then we will never escape the whirling cyclone of sin that currently holds us in its grip, pulling us to the dark center. But imagine the difference if we were uneasy when not partaking in Christ? Then this natural tendency to avoid uneasiness would be harnessed for good.
The only way that a change of desire like this can happen is by direct intervention of God. And that is what I ask for.