Do you want to know why
we won't be successful in a
certain ministry? It's because we rely
on ourselves. This preacher, that
Superior, or that confessor relies
too much on his own prudence,
knowledge, and intelligence. And what
does God do? He withdraws
from him and leaves him on his own; and
even though he works, whatever he does produces no fruit, in order to
make him aware of his own
uselessness and so that he’ll learn from
personal experience that,
whatever talent he may have, he can do
nothing without God. (SV XI, 31)