By Father Schall: Any friendship, especially God’s, must be chosen on both sides. Evil thus is found in a being that need not choose evil but does.
The Fall of the Rebel Angels by Pieter Bruegel the Elder, 1562 [Museum of Fine Arts, Brussels]
The “thou shalts” and “thou shalt nots” of the Ten Commandments were given to us, Chesterton thought, so that, knowing the few things we should avoid, we could enjoy the millions of other things that were quite all right to do. The Commandments were not given to cramp our style. They broaden almost infinitely the scope of what is out there for us to know and accomplish. The things we should not do, when we do them anyhow, usually, if we are honest with ourselves, turn into ashes in our mouths. They make us less than what we ought to be and know we ought to be.
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Source: On Evil – The Catholic Thing