You are the sole and absolute ruler of the known world. Your eldest son has come of age, married, and fathered a son. To celebrate this momentous event, you decide to declare an amnesty for all criminals, except for those convicted of specific, particularly heinous offenses. Which crimes do you choose to exempt?
Well, if you're Constantine the Great in AD 322, your choices might be considered a bit odd by contemporary standards. According to Ramsay MacMullen's biography of the emperor,
Constantine expressed his pride and happiness through a general amnesty to all criminals "except enchanters, murderers, and adulterers," those being beyond the pale.
"The list," Prof. MacMullen dryly observes, "throws an interesting light on morals and mores of the time."