O tempora, o mores!, meaning “Oh the times! Oh the customs!” – these were the words Cicero uttered against Catilina.
In his speech, Cicero turns to Catilina, who had previously tried to murder him. The great Roman speaker condemns corruption and deplores the corruption of morals. Cicero was frustrated that despite much evidence of Catilina’s guilt, he wanted to overthrow the republic and kill Cicero, and that although the so-called senatus consultum ultimum (undertaken at times of extraordinary internal threat) was declared, Catilina has still not been sentenced to death.
Cicero in his speech argued that the consuls in the past were more determined, even when there were no such strong indications of the suspect’s guilt.
Currently sentence O tempora, o mores! is usually cited with a hint of irony.