Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[284] When they had taken this resolution, and that by common consent, they went into the theater, hoping that, in the first place, Herod himself could not escape them, as they should fall upon him so unexpectedly; and supposing, however, that if they missed him, they should kill a great many of those that were about him; and this resolution they took, though they should die for it, in order to suggest to the king what injuries he had done to the multitude. These conspirators, therefore, standing thus prepared beforehand, went about their design with great alacrity; but there was one of those spies of Herod, that were appointed for such purposes, to fish out and inform him of any conspiracies that should be made against him, who found out the whole affair, and told the king of it, as he was about to go into the theater. So when he reflected on the hatred which he knew the greatest part of the people bore him, and on the disturbances that arose upon every occasion, he thought this plot against him not to be improbable. Accordingly, he retired into his palace, and called those that were accused of this conspiracy before him by their several names; and as, upon the guards falling upon them, they were caught in the very fact, and knew they could not escape, they prepared themselves for their ends with all the decency they could, and so as not at all to recede from their resolute behavior, for they showed no shame for what they were about, nor denied it; but when they were seized, they showed their daggers, and professed that the conspiracy they had sworn to was a holy and pious action; that what they intended to do was not for gain, or out of any indulgence to their passions, but principally for those common customs of their country, which all the Jews were obliged to observe, or to die for them. This was what these men said, out of their undaunted courage in this conspiracy. So they were led away to execution by the king's guards that stood about them, and patiently underwent all the torments inflicted on them till they died. Nor was it long before that spy who had discovered them was seized on by some of the people, out of the hatred they bore to him; and was not only slain by them, but pulled to pieces, limb from limb, and given to the dogs. This execution was seen by many of the citizens, yet would not one of them discover the doers of it, till upon Herod's making a strict scrutiny after them, by bitter and severe tortures, certain women that were tortured confessed what they had seen done; the authors of which fact were so terribly punished by the king, that their entire families were destroyed for this their rash attempt; yet did not the obstinacy of the people, and that undaunted constancy they showed in the defense of their laws, make Herod any easier to them, but he still strengthened himself after a more secure manner, and resolved to encompass the multitude every way, lest such innovations should end in an open rebellion.