"The Screwtape Letters" de C.S. Lewis (1942)

At the very least, they can be persuaded that the bodily position makes no difference to their prayers; for they constantly forget […] that they are animals and that whatever their bodies do affects their souls.

He wants men to be concerned with what they do ; our business is to keep them thinking about what will happen to them. 

He wants them to learn to walk and must therefore take away His hand; and if only the will to walk is really there, He is pleased even with their stumbles.

You are much likely to make your man a sound drunkard by pressing drink on him as an anodyne when he is dull and weary than by encouraging him to use it as a means of merriment among his friends when he is happy and expansive.

The man who truly and disinterestedly enjoys any one thing in the world, for it’s own sake, and without caring two pence what other people say about it, is by that very fact forearmed against some of our subtlest modes of attack.

This, indeed, is probably one of the Enemy’s motives for creating a dangerous world – a world in which moral issues really come to the point. He sees as well as you do that courage is not simply one of the virtues, but the form of every virtue at the testing point, which means, at the point of highest reality. A chastity or honesty or mercy which yields to danger will be chaste or honest or merciful only on conditions. Pilate was merciful till it became risky.