The Seventh Day Adventist Church of Tonga or Siasi ʻAhofitu is a church in Tonga

Tonga

Tonga, officially the Kingdom of Tonga , is a state and an archipelago in the South Pacific Ocean, comprising 176 islands scattered over of ocean in the South Pacific...

. The Seventh-day Adventist used to worship on Saturday (Sabbath) until the International Date Line was officially drawn to the west of Tonga. This changed the worship from Saturday to Sunday. For the first time in history, the SDA church of Tonga became the first among the Seventh-day Adventist churches to celebrate sabbath on Sunday. They claim that since the International Dateline changed it doesn't affect their true Sabbath

Sabbath

Sabbath in Christianity is a weekly day of rest or religious observance, derived from the Biblical Sabbath.Seventh-day Sabbath observance, i.e. resting from labor from Friday sunset to Saturday sunset, is practiced by seventh-day Sabbatarians...

 worship, believing that Sunday in Tonga

Tonga

Tonga, officially the Kingdom of Tonga , is a state and an archipelago in the South Pacific Ocean, comprising 176 islands scattered over of ocean in the South Pacific...

 is actually Saturday in Fiji

Fiji

Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...

. They also claim Monday is the first day of the week and Sunday is the seventh day, different from overseas reckoning. Originally Sunday

Sunday

Sunday is the day of the week between Saturday and Monday. For most Christians, Sunday is observed as a day for worship of God and rest, due to the belief that it is Lord's Day, the day of Christ's resurrection....

is the first day of the week.

Criticism

SDA Church of Tonga had been criticized by other Seventh-day Adventist churches for worshiping on Sunday instead of Saturday. According to the doctrine of the Seventh-day Adventist theology that one day there will be enforcement to keep the Sunday law, known as the mark of the beast. The majority of the Seventh-day Adventist members believe that Sunday must be avoided due to this belief, therefore, they criticized the SDA Church of Tonga for misleading.