cbk's post was excellent imo. I was a former CoC member, and as was stated earlier, this practice varies from congregation to congregation. In principle, they are right but in application, I think the extreme position has neglected the theology behind it.
The Pascha, salvation, newness of life that is celebrated in Christianity should not be limited to just one day, or even the "Lord's day", but always celebrated. but the nature of things in heaven, where Christ has entered into the holy of holies, and sat down at the right hand of God for eternity, is different than this world which is still in bondage to time.
We as Christians should recognize that God has divided the time for us into years/seasons days and hours. One of the purposes and acts of creation. And though time flows by, God has given us an eternity "in time" through days, and seasons and festivals, that repeat day after day, year after year.
Prayer, worship, and Pascha all exist in time but when participated in, should bring us into enternity, or rather take us to that moment on Calvary. Thus these things bing part of the fabric of time, transcend it, giving us a fortatse of things eternal themselves.
Thus the early church in recognizing this had broken all aspects of daily life down into revolving around the crucufixtion and ressurection of Christ. Not just a day of the week or year, but prescribed worship to the hour of every day. ie; the 6th hour of the day (every day) is the hour of Christ's crucifixion, the ninth hour is the hour of His death etc. This extends to the days of the week, wednessday being the day He was betrayed, Friday being the day of His crucufixion, Sunday-the resurrection. This takes place through all of the "divisions" created by God throught out the year, whcih is an "eternal" cycle. (thus the passover being institued as "forever" in exodus, is still observed, and will be for all time).
In liturgical worship the phrase "today" is used quite often to emphasize this point; "Today, He who hung the earth upon the waters is hung on a tree."
Breaking down time, and bringing us into eternity, or rather placing us at the foot of the cross. The entire year should revolve around Christ, from the hours, to the days of the week, to the seasons, as God has ordained.
Therefore;
So at midnight or the early morning hour I remeber the resurrection.
On sunday I remeber the resurrection.
On pascha I remeber the resurrection.
By doing this, the believer subjugates everything, including time itself to the Lord, as opposed to giving time to the world.
Sorry for the long ramble....