Court decides only Muslims can use the term "Allah" in what critics say is an attempt to appease right-wing extremist supporters of embattled Prime Minister Najib Razak

Vincent Thian / AP Malaysian Muslim demonstrators pray outside the Court of Appeal in Putrajaya, outside Kuala Lumpur, on Oct. 14, 2013

Allah can no longer be used by a Christian newspaper in Malaysia to refer to God after a landmark court ruling on Monday, reversing a decision made four years previously that maintained the term transcended different faiths.

“It is my judgment that the most possible and probable threat to Islam, in the context of this country, is the propagation of other religions to the followers of Islam,” said chief judge Mohamed Apandi Ali, announcing the change.

The panel of three judges was unanimous in their decision that the use of Allah by the Roman Catholic Herald newspaper constituted a threat to the sanctity of Islam, as defined in the federal constitution. The Herald editor the Rev. Lawrence Andrew said he was “disappointed and dismayed,” vowing to appeal.

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The issue is contentious. The previous 2009 ruling was followed by a spate of attacks on churches, and critics fear the issue is once again being used to stoke religious tensions in the Muslim-majority Southeast Asian nation. “Narrow-minded and prejudiced people are creating an atmosphere of hatred,” Mujahid Yusof Rawa, an MP for Malaysia’s opposition Pan-Malaysian Islamic Party, tells TIME.

According to the Rev. Eu Hong Seng, chairman of the Christian Federation of Malaysia, “The Bahasa Malaysia–speaking Christians have been using the word Allah before and after the independence of Malaya and the formation of Malaysia.”

Plenty of academic evidence suggests that Allah has also been used by Christians and Jews in Arabia for generations. “And what about the 10 [million] to 12 million Arab Christians today? They have been calling God ‘Allah’ in their Bibles, hymns, poems, writings, and worship for over 19 centuries,” says Fouad Accad in his book Building Bridges: Christianity and Islam, which examines commonality between the different faiths.

Allah was common parlance even before the birth of Islam in the sixth century. “Arabs used the word ‘Allah’ for the supreme being before the time of Muhammad,” writes Kenneth J. Thomas, a United Bible Societies translation consultant based in New York. “Inscriptions with ‘Allah’ have been discovered in Northern and Southern Arabia from as early as the fifth century B.C.”

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With Christians in the neighboring Indonesia still allowed to use the term, many ponder what is behind the Malaysian U-turn. Mujahid believes this latest ruling is part of a “dynamic” of Malay right-wing appeasement after Prime Minister Najib Razak was returned to power with a slim majority.

“Malaysia is not prepared yet for such mature interfaith relationships, since the word Allah is still seen as very sensitive to Muslims,” he laments. “But I don’t think Muslims are that weak that they are going to convert to Christianity by hearing the word Allah said by a Christian.”

Ethnicity has been a key facet of Malaysian politics since colonial times, and increasingly so after 1971, when affirmative action for the bumiputra, or “sons of the soil” as the Malay and smaller indigenous minorities call themselves, was introduced in the wake of bloody race riots.

Ethnic Malays make up around two-thirds of Malaysia’s 28 million people. Chinese and Indians control much of the wealth and make up around 22% and 7% of the population respectively. About 9% of Malaysians are Christian.

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