Nicea is commemorated every year right after Pascha. But it is too important to be commemorated only then. In a sense we commemorate Nicea every time we say the Creed—i.e. at least every Sunday. For the Creed is not simply one item in the Liturgy, one piece of furniture within the ecclesiastical house. It constitutes the very walls of that house.
If one disbelieves in Christ and Pascha, then our cultural of denial of death makes good sense. We can’t do anything about the fearful fate which awaits us, so why think about it? Eat, drink, be merry, and watch television. But if what the Church says about Christ and Pascha is true, we don’t need the lies or the denial.