most churches which use the old (julian) calendar are "not" old calendarists: they remain in communion with the eastern orthodox churches that use the new calendar (the revised julian calendar). thus, to be "old calendarist" or "old calendar" is not the same thing as being "on the old calendar". the russian orthodox church, for instance, is not old calendarist (or old calendar), but it is on the old calendar. there are a great many eastern orthodox christians who are (or who belong to churches that are) "on the old calendar", but far fewer in number are the eastern orthodox christians who are "old calendar" or "old calendarist."