"Direct, straight-line, intervening power does, of course, have many uses. With it, you can lift the spaghetti from the plate to your mouth, wipe the sauce off your slacks, carry them to the dry cleaners, and perhaps even make enough money to ransom them back. Indeed, straight-line power ("use the force you need to get the result you want") is responsible for almost everything that happens in the world. And the beauty of it is, it works. From removing the dust with a cloth to removing your enemy with a .45, it achieves its ends in sensible, effective, easily understood ways.
"Unfortunately, it has a whopping limitation. If you take the view that one of the chief objects in life is to remain in loving relationships with other people, straight-line power becomes useless. Oh, admittedly, you can snatch your baby boy away from the edge of a cliff and not have a broken relationship on your hands. But just try interfering with his plans for the season when he is twenty, and see what happens, especially if his chosen plans play havoc with your own. Suppose he makes unauthorized use of your car, and you use a little straight-line verbal power to scare him out of doing it again. Well and good. But suppose further that he does it again anyway -- and again and again and again. What do you do next if you are committed to straight-line power? You raise your voice a little more nastily each time till you can't shout any louder. And then you beat him (if you are stronger than he is) until you can't beat any harder. Then you chain him to a radiator till....But you see the point. At some very early crux in that difficult, personal relationship, the whole thing will be destroyed unless you -- who, on any reasonable view, should be allowed to use straight-line power -- simply refuse to use it; unless, in other words, you decide that instead of dishing out justifiable pain and punishment, you are willing, quite foolishly, to take a beating yourself.
"But such a paradoxical exercise of power, please note, is a hundred and eighty degrees away from the straight-line variety. It is, to introduce a phrase from Luther, left-handed power...Left-handed power is precisely paradoxical power: power that looks for all the world like weakness, intervention that seems indistinguishable from nonintervention."
(Kingdom, Grace, Judgment, pp. 18-19)