In this case, it is a biblical quotation from the First Epistle of Peter (5:8): Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour. The French title is more apposite, referring to an aspect of the werewolf myth that plays some part in the story, that the werewolf when in human form is wearing the wolfskin inside out. An alleged werewolf may therefore be exposed by cutting (generally fatally), when wolf-hair will be seen in the wound.
In this scenario, it's a biblical quote from First Epistle of Peter (5:8): Be alert and cautious; your adversary Satan behaves like a roaring lion seeking prey. The French title is more relevant, alluding to a werewolf myth where the creature wears wolf skin inside out when human. A suspected werewolf could be identified by cutting them, revealing hair from wolves in the wound.