“Uma espada obriga a outra a ficar na bainha.”
One sword keeps another in the sheath
"Jacula Prudentum" in: "The Poetical Works of George Herbert: With Life, Critical Dissertation and Explanatory Notes" - Página 314 http://books.google.com.br/books?id=b6IpXPlBKFkC&pg=PA314, de George Herbert, George Gilfillan - Publicado por Appleton,1854 - 328 páginas