World Building Timeless or Timely

Are the cultural elements that the alien culture you are writing values considered timeless or timely? Does the cultural see morals as progressing from one thing to another or do they see morals as  a timeless monolith? 
Do the moral referees of your culture say, "You can't do that! It's [insert date]!" 
Do the moral referees of your culture say, "This is the way it has always been." 
Is your culture in a state of onward change or of cyclic repetition? 
Take all or some of these questions and apply them to any moral aspect; murder, theft, lying. See what happens.