Time is an interesting construct. We divide it up into minutes, hours, days, and years. When an event of cataclysmic proportions takes place in our lives, we divide it into Before and After. Before the wedding; After the art show; Before the divorce; After the kids moved to college. Much like Dionysius, who devised a system of counting time to do away with the memory of a ruthless emperor.
“The first year in Dionysius’ Easter table, “Anno Domini 532,” followed the year “Anno Diocletiani 247.” Dionysius made the change specifically to do away with the memory of this emperor who had been a ruthless persecutor of Christians.” – via LiveScience