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

[70] However, the execution of Cherea's designs was put off from day to day, by the sloth of many therein concerned; for as to Cherea himself, he would not willingly make any delay in that execution, thinking every time a fit time for it; for frequent opportunities offered themselves; as when Caius went up to the capitol to sacrifice for his daughter, or when he stood upon his royal palace, and threw gold and silver pieces of money among the people, he might be pushed down headlong, because the top of the palace, that looks towards the market-place, was very high; and also when he celebrated the mysteries, which he had appointed at that time; for he was then no way secluded from the people, but solicitous to do every thing carefully and decently, and was free from all suspicion that he should be then assaulted by any body; and although the gods should afford him no divine assistance to enable him to take away his life, yet had he strength himself sufficient to despatch Caius, even without a sword. Thus was Chorea angry at his fellow conspirators, for fear they should suffer a proper opportunity to pass by; and they were themselves sensible that he had just cause to be angry at them, and that his eagerness was for their advantage; yet did they desire he would have a little longer patience, lest, upon any disappointment they might meet with, they should put the city into disorder, and an inquisition should be made after the conspiracy, and should render the courage of those that were to attack Caius without success, while he would then secure himself more carefully than ever against them; that it would therefore be the best to set about the work when the shows were exhibited in the palace. These shows were acted in honor of that Caesar ¹ who first of all changed the popular government, and transferred it to himself; galleries being fixed before the palace, where the Romans that were patricians became spectators, together with their children and their wives, and Caesar himself was to be also a spectator; and they reckoned, among those many ten thousands who would there be crowded into a narrow compass, they should have a favorable opportunity to make their attempt upon him as he came in, because his guards that should protect him, if any of them should have a mind to do it, would not here be able to give him any assistance.