Is then no nook of English ground secure From rash assault? - William Wordsworth

In that sweet mood when pleasant thoughts Bring sad thoughts to the mind.

Words are too awful an instrument for good and evil to be trifled with: they hold above all other external powers a dominion over thoughts. If words be not (recurring to a metaphor before used) an incarnation of the thought but only a clothing for it, then surely will they prove an ill gift; such a one as those poisoned vestments, read of in the stories of superstitious times, which had power to consume and to alienate from his right mind the victim who put them on. Language, if it do not uphold, and feed, and leave in quiet, like the power of gravitation or the air we breathe, is a counter-spirit, unremittingly and noiselessly at work to derange, to subvert, to lay waste, to vitiate, and to dissolve.

I've heard of hearts unkind, kind deeds
With coldness still returning;
Alas! the gratitude of men
Has oftener left me mourning.