From Tacitus’ Histories (4.52, text and translation from the Loeb edition by Clifford Moore) – a lesson that loops back to the present, as does much of Tactius.
We are growing weak, fellow-senators, and are no longer that senate which after Nero had been cut down demanded that his informers and tools should be punished according to the custom of our forefathers. The fairest day after a bad emperor is the first.
Elanguimus, patres conscripti, nec iam ille senatus sumus qui occiso Nerone delatores et ministros more maiorum puniendos flagitabat. Optimus est post malum principem dies primus.