The War Prayer
Is it one prayer? No, it is two – one uttered, the other not. Both have reached the ear of Him Who heareth all supplications, the spoken and the unspoken. Ponder this – keep it in mind. If you would beseech a blessing upon yourself, beware! lest without intent you invoke a curse upon a neighbor at the same time. If you pray for the blessing of rain upon your crop which needs it, by that act you are possibly praying for a curse upon some neighbor's crop which may not need rain and can be injured by it.
— Mark Twain, The War Prayer
It is an essay packing some heat.