Vocation, Book of Isaiah

Yet just as from the heavens
the rain and snow come down
And do not return there
till they have watered the earth,
making it fertile and fruitful,
Giving seed to the one who sows
and bread to the one who eats,

So shall my word be
that goes forth from my mouth;
It shall not return to me empty,
but shall do what pleases me,
achieving the end for which I sent it.

+ The Book of Isaiah 55,10-11

http://www.usccb.org/bible/isaiah/55