This sort of thing went on continually, and provided him a poor atmosphere in which to do his great and important work. As he grew older, he retired more and more. He trusted in his minister Sejanus who had once heroically save his life: an exceedingly able, but unfortunately also an exceedingly wicked man. Sejanus became his link with Rome and the senate; and used that position, and the senate’s incompetence, to gather into his own hands a power practically absolute in home affairs. Home affairs, be it always remembered, were what the Princeps expected the senate to attend to: their duty, under the constitution. Instead, however, they fawned on Sejanus ad lib. Sejanus murdered Tiberius’ son Drusus, and aspired to the hand of Livilla, his widow: she was the daughter of Germanicus and Agrippina; and she certainly, and Agrippina probably, were accessories to the murder of Drusus. For Agrippina was obsessed with hatred for Tiberius: with the idea that he had murdered her husband, and with thirst for revenge. Sejanus was thus in a fair way to the ends of his ambition: to be named the successor to the Principate.
Then Tiberius found him out; and sent a message to a senate engaged in Sejanus-worship, demanding the punishment of the murderers of Drusus.
Sejanus had built up his power by fostering the system of delation. There was no public prosecutor in the Roman system: when any wrong had been done, it was anyone’s business to prosecute. The end of education was rhetoric, that you might get on in life. The first step was to bring an accusation against some public man, and support it with a mighty telling speech. If you succeeded, and killed your man,—why, then your name was made. On this system, with developments of his own, Sejanus had built; had employed one half of Rome informing against the other. It took time to bring about; but he had worked up by degrees a state of things in which all went in terror of him;