Screwtape offers a helpful image:
Think of your man /as a series of concentric circles,
his will /being the innermost, his intellect /coming next, and finally his fantasy.
You can hardly hope, at once, [to exclude from all the circles everything //that smells of the Enemy]:
but you must keep on [shoving all the virtues outward /till they are finally located in the circle of fantasy,
and all the desirable qualities /inward /into the Will].
* to exclude /from all the circles [everything //that smells of the Enemy]:
* shoving [all the virtues outward /till they are finally located in the circle of fantasy],
and (shoving) all the desirable qualities /inward /into the Will].
It is only in /so far as they reach the Will
and are there /embodied in habits //that the virtues are really fatal to us.
(I don’t, of course, mean [what the patient mistakes for his Will, the conscious fume and fret of resolutions and clenched teeth],
but the real centre, what the Enemy calls the Heart.)
[All sorts of virtues /painted in the fantasy or approved by the intellect or even, in some measure, loved and admired],
will not keep a man from Our Father’s house:
indeed they may make [him] [more amusing] /when he gets there.
From The Screwtape Letters
Compiled in A Year with C.S. Lewis