And on the seventh day he rested. Except for that week that had only six days.

Samoa, whose constitutional motto says the place was "founded on God", is brawling over which day it was that the Christian deity took a day off.

While it is causing amusement to most of the 189,000 Samoans, it is deadly serious for the 3.5 per cent who belong to the Seventh Day Adventist Church and were united in the belief that God rested on Saturday.

That was until Prime Minister Tuila'epa Sailele decided to move the dateline so that Samoa could be in the same day as New Zealand.

To do so he abolished Friday, December 30, 2011, and Samoa - and shortly after Tokelau and Wallis and Futuna - were west of the dateline.

The resulting shuffle of dates and days resulted in Samoan Adventists switching services to a Sunday because that ended up being the seventh day of that particular week. And so on.

"The practical result in terms of Sabbath keeping is that Sunday not Saturday has become the seventh day of the week," Pastor Uili Solofa said at the time.

Not so says the world SDA president, Ted Wilson, who last month, in an obscure message, repeatedly said the Sabbath was Saturday.

"The mark of the beast - observance of a day other than the seventh-day Sabbath - is an institution that clearly sets forth the authority of the beast," he said and without naming Samoans he said "one church boldly boasts that it has changed the seventh-day Sabbath instituted at Creation from Saturday to Sunday."

It's no light thing says Wilson: "Apostate religious leaders will not be able to refute scriptural evidence for the sacredness of Saturday, and this will fill them with anger. As a result, Sabbath keepers will be persecuted and imprisoned."

A breakaway group, the Samoa Saturday Sabbath Keepers (SSSK), is fighting back but a schism has set in and the main SDA church bans the Saturday-ists.

Around 40 families seem to have signed up with SSSK and hold covert Saturday services. They note, with disapproval, that the other Adventists are now praying on the same day as Roman Catholics and Protestants.

The New York-founded Seventh Day Adventists base their practice on a message from a "third angel" in the Book of Revelations who, they say, warned against Sunday as a sacred day, saying it was the mark of the beast.

Wilson's proclamation that Samoans must have a Saturday Sabbath has not settled anything and it is now likely to end up in Samoa's courts.

Judges have some useful precedents from 1582 when Pope Gregory XIII abolished 10 days in the switch from the Julian calendar to the Gregorian or Christian version.

Mythology says people rioted over that; history shows they did not. But it is getting warm in Samoa.