The Christian couple who had their five children removed by Norway's child protection services are undertaking a 40-day fast as they wait to hear whether their children will be returned to their custody.

Marius and Ruth Bodnariu have released a statement confirming they were in court this week to urge the authorities to allow their children to return home.

"We are at the end of the Court procedures that took place on March 14 and 15. We are grateful to all of you for fasting and praying and for your support!" the statement said.

"We await the decision of the Court with the knowledge that we've done everything humanly possible, understanding that all things are in God's hands and trusting His good plans for our lives!

"We continue to pray and fast as scheduled for 40 days before April 16!"

The Bodnarius said they expect a decision to be made in the next few weeks, possibly during the first week of April.

Marius Bodnariu is a Romanian married to Ruth, a Norwegian. Formerly members of the Philadelphia Pentecostal Church in Bucharest, they moved to Norway 10 years ago to start a family there and live in Naustdal on the west coast. Their children, two daughters and three sons, were removed in November 2015 on suspicion of parental child abuse and religious indoctrination after one of the daughters told her headteacher that Marius and Ruth spanked the children as a disciplinary measure.

Corporal punishment is illegal in Norway, and schools are obliged to report it.

Peter Costea, a Texas-based Romanian lawyer monitoring the case, has previously said he did not believe the family's Pentecostal faith was a factor in the children's removal. However he last month revealed newly obtained records that he said showed the authorities were concerned the Bodnarius had "their own faith and way of upbringing when it comes to religion".

"They plainly state that Barnevernet [Norway's child welfare services] 'is worried that this is a way of upbringing which is justified by the Bible'," Costea, president of the Alliance for Romania's Families, said.

"The documents also mention that the children were 'brought up to respect God and their parents' values.' Barnevernet interpreted this as a possible conflict between the children's assumed inability to live up to their parents' value expectations and faith and that the parents' religion could create an 'inner conflict' in the children and a stressful family environment. Religion is bad for children, Barnevernet's minutes seem to say, and too much religion is lawful justification for snatching children away from their parents."

The case has gained worldwide attention, and a petition calling on the Bodnarius to be reunited with their children, who are currently in foster care, has gained almost 60,000 signatures.