Muslim demonstrators gathered outside the Malaysian Court of Appeal as judges prepare to rule on who can use the word 'Allah'.
Inside the court three Muslim judges unanimously agreed it's exclusively Muslim and banned a Christian newspaper from using it to refer to God.
Lawyers for the Catholic newspaper The Herald argued the term pre-dated Islam and has been used for centuries by Christians in parts of the country.
Herald editor Lawrence Andrew condemned the ruling.
(SOUNDBITE)(English) LAWRENCE ANDREW, EDITOR OF CATHOLIC NEWSPAPER 'THE HERALD' SAYING:
"God is an integral part of every religion we have and Allah is a term in the Middle East and in Indonesia. It's a term both for Christians and Muslims. You cannot say that all of a sudden it's not an integral part. Malay language is a language that has many borrowed words. Allah also is a borrowed word."
Outside the court the protesters welcomed the decision which overturns one in 2009 by a lower court.
(SOUNDBITE)(Bahasa Malaysia) JAFRIZAL AHMAD JAAFAR, PROTESTER, SAYING:
"As Muslims it's our religious duty to protect the world 'Allah'. That's why we are here, to show our support for this holy word."
Lawyers for The Herald say they'll appeal against Monday's ruling.
But it's come at a time of heightened religious and ethnic tension in Malaysia.
Prime Minister Najib Razak's trying to consolidate his support among ethnic Malays who are Muslim by law.
His government is boosting affirmative action policies for ethnic Malays, and reversing liberal reforms aimed at the broader population.