Classic Poem

I spoke a word
And no one heard:
I wrote a word
And no one cared:
But after a half a score of years
It blossomed in a fragrant deed.
Preachers and teachers all are we,
Sowers of seed unconsciously.
Our hearts are beyond our ken,
Yet all we give may come again
With usury of joy and pain;
We never know
To what one little word may grow
See to it, then, that all your seed
Be such as bring forth noble deed.