many areas of Europe use a calendar that has Sunday as the seventh day of the week. Does anyone know, in those areas that use that calendar
Europeans are as confused as everyone else. Microsoft Windows shows Sunday as the seventh day of the week. The New York Times accounts it likewise. Many calendars available for purchase all over the world do so. One might have a calendar in the kitchen that has one usage, another in the study that has the other. I suspect that most people could not say definitively what day is the first of the week, or even if there
is a first day- or even if there is a week, for that matter. It's an arbitrary, man-made device, though the lunar month may have much to do with its original popularity, which dates back to pre-Abrahamic Babylonia. The biblical command to the Israelites to keep a seven-day week was very arguably of no inherent significance, but was probably respectful reference to the week that Abraham and the other patriarchs had inherited from Babylonia, and stood in contrast to the week of Egypt, which had ten days. This sudden change would have been a timely reminder to Israelites of the importance of faith rather than law, because the patriarchs were justified by their faith, before there was law.
on what day they hold their weekly worship services?
Some meet several times in a week. Some on, say, a Wednesday, because it is convenient for them. There are those who meet every day, as did the disciples in Jerusalem. The majority of those who make claim to be Christians attend for an hour, though usually less, on Sundays, or rather, occasional Sundays.
If they hold it on the seventh day, do they also do anything special on the first day in celebration of the resurrection?
I don't believe so. They have no genuine reason for celebrating Jesus' resurrection on any particular day. There is no apostolic command to do so. It can be said that Jesus rose on the day after the Jewish sabbath because it was
not the Sabbath, not because that day had inherent significance. In any case, both in Judea and in the Roman Empire the day on which Jesus rose was a working day, and that is the Scriptural precedent, if there is insistence on keeping any day special. At the time of Jesus' resurrection, the Empire had recently begun the change from an eight-day week to a seven-day week, no doubt for commercial purposes, so even that coincidence has probably deceived people into thinking that a seven-day week is somehow a divine institution, permitting a sort of quasi-sabbath on one of its days.
