Knock the little bastards' brains out.

I stumbled onto this quote by C.S. Lewis in his Reflections on the Psalms concerning the cursing psalms in the Scriptures:

I know things in the inner world which are like babies; the infantile beginnings of small indulgences, small resentments, which may one day become dipsomania or settled hatred, but which woo us and wheedle us with special pleadings and seem so tiny, so helpless that in resisting them we feel we are being cruel to animals. They begin whispering to us, "I don't ask much, but", or "I had at least hoped", or "you owe yourself some consideration". Against all such pretty infants (the dears have such winning ways) the advice of the Psalm is the best: knock the little bastards' brains out. And "blessed" he who can, for it's easier said than done.

The same interpretation is given in the early Fathers of the Church as can be seen here in St John Cassian's Institutes: "It behooves us as well to destroy the sinners in our bed - namely, our fleshly feelings - on the morning of their birth, as they emerge, and, while they are still young, to dash the children of Babylon against the rock. Unless they are killed at a very tender age they will, with our acquiescence, rise up to our harm as stronger adults, and they will certainly not be overcome without great pain and effort" (6.13.2).