Some see the origin of religion in human violence: violence needs forgiveness and forgiveness needs authority. In the context of describing his poetry, Ted Hughes implicitly illuminates the difference between human and animal killing.
these creatures [Hawk, Pike and Bull] are “at rest in the law” – obedient, law-abiding, and are as I say the law in creaturely form. If the Hawk and the Pike kill, they kill within the law and their killing is a sacrament in this sense. It is an act not of violence but of law.