Archibald Lampman - Good Speech

Think not, because thine inmost heart means well,
Thou hast the freedom of rude speech: sweet words
Are like the voices of returning birds
Filling the soul with summer, or a bell
That calls the weary and the sick to prayer.
Even as thy thought, so let thy speech be fair.

Archibald Lampman

http://www.poemhunter.com/poem/good-speech/