In characterizing the book's overarching thematic concerns, Randall Jarrell wrote: The poems understand the world as a sort of conflict of opposites. In this struggle one opposite is that cake of custom in which all of us lie embedded like lungfish--the statis or inertia of the stubborn self, the obstinate persistence in evil that is damnation. Into this realm of necessity the poems push everything that is closed, turned inward, incestuous, that blinds or binds: the Old Law, imperialism, militarism, capitalism, Calvinism, Authority, the Father, the "proper Bostonians," the rich who will "do everything for the poor except get off their backs." But struggling within this like leaven, falling to it like light, is everything that is free or open, that grows or is willing to change: here is the generosity or openness or willingness that is itself salvation, of the Grace that has replaced the law, of the perfect liberator whom the poet calls Christ.