Excerpts from "Poetry and Marriage: The Use of Old Forms" by Wendell Berry:
Form, crudely or stupidly used, may indeed be inimical to freedom. Well used, it may be the means of earning freedom, the price of admission or permission, the enablement to be free. But the connection may be even closer, more active and interesting, than that; it may be that form, strictly kept, enforces freedom. The form can be fulfilled only by a kind of abandonment to hope and to possibility, to unexpected gifts. The argument for freedom is not an argument against form. Form, like topsoil (which is intricately formal), empowers time to do good.
Properly used, a verse form, like a marriage, creates impasses, which the will and present understanding can solve only arbitrarily and superficially. These halts and difficulties do not ask for immediate remedy; we fail them by making emergencies of them. They ask, rather, for patience, forbearance, inspiration—the gifts and graces of time, circumstance, and faith. They are, perhaps, the true occasions of the poem; occasions for surpassing what we know or have reason to expect. They are points of growth, like the axils of leaves. Writing in a set form, rightly understood, is anything but force and predetermination. One puts down the first line of the pattern in trust that life and language are abundant enough to complete it. Rightly understood, a set form prescribes its restraint to the poet, not to the subject.
Marriage too is an attempt to rhyme, to bring two different lives—within the one life of their troth and household—periodically into agreement or consent. The two lives stray apart necessarily, and by consent come together again: to "feel together," to "be of the same mind." Difficult virtues are again necessary. And failure, permanent failure, is possible. But it is this possibility of failure, together with the formal bounds, that turns us back from fantasy, wishful thinking, and self-pity into the real terms and occasions of our lives.
It may be then that form serves us best when it works as an obstruction, to baffle us and deflect our intended course. It may be that when we no longer know what to do, we have come to our real work and when we no longer know which way to go, we have begun our real journey. The mind that is not baffled is not employed. The impeded stream is the one that sings.