Titus Livius (Livy), The History of Rome, Book 9
Benjamin Oliver Foster, Ph.D., Ed.

10. both the cause itself and the speaker greatly stirred the Conscript Fathers and the others present, including even the tribunes of the plebs, who declared that they would obey the senate, and having forthwith [2??] resigned their office were delivered over to the fetials to be led with the rest to Caudium. when the senate had acted on this motion, it somehow seemed as though day had dawned upon the State. [3] Postumius was on all men's lips; they extolled him to the skies, and compared his conduct to the devotion of Publius Decius, the consul,¹ and to other glorious deeds. [4] The state, they said, had emerged —thanks to his wisdom and his services —from a slavish peace; he was freely giving himself up to the tortures of a resentful foe, that he might make expiation for the Roman People. [5] men thought of nothing but war and arms. [6] would ever the hour come, they asked, when they might encounter the Samnites, sword in hand?

in a city ablaze with wrath and hate, the levy was almost wholly made up with volunteers. The same soldiers were enrolled into new legions, and the army marched on Caudium. [7] before them went the fetials, who, when they had come to the gate, bade the guarantors of peace be stripped and their hands be bound behind their backs. [8] as the officer, awed by the dignity of Postumius, would have left him loosely [p. 201]bound, “nay, draw the thong tight,” he exclaimed,² “that the surrender may be duly carried out.” then, on arriving at the assembly of the Samnites and the tribune of Pontius, Aulus Cornelius Arvina the fetial³ spoke as follows: [9] "whereas these men, unbidden by the Roman People of the Quirites, have guaranteed that a treaty should be ratified, and by so doing have committed an injury; to the end that the Roman People may be absolved of heinous guilt, I deliver up these men to you. [10] as the fetial spoke these words, Postumius thrust his knee into the other's thigh, with all the force he could summon up, and proclaimed in a loud voice that he was a Samnite citizen, who had maltreated the envoy in violation of the law of nations, whereby the Romans would make war with the better right.