Jesus spoke Aramaic. And the word for ‘God’ in his language is ‘Allah’.
We have an ancient version of the Bible, the Peshitta, written in an Eastern Aramaic dialect. To be clear, I cannot read these texts and so am reliant on the scholarship of others.
The connections between words for ‘God’ are clear. The Proto-Semitic stem for “God” is *ʼil-(āh)-. Eloi (Mark 15:34) is, then, connected to the Aramaic, “Alaha”, and to the Arabic, “Allah”. And clearly related to the Hebrew word for God, Elohim.
“Allahu Akbar”, then, is not particularly Islamic – it is simply “God is great” in Arabic, and used by Christians who use Arabic in their worship.
Archbishop Sebastia Theodosios is the only Orthodox Christian archbishop from Palestine stationed in Jerusalem and the Holy Land. He responded to the question: “To a Western mind, Allahu Akbar sounds like a threat. What do Christians of the Holy Land think about them?”
We Christians also say Allahu Akbar. This is an expression of our understanding that the Creator is great. We don’t want this phrase to be related to terrorism and crimes.
We refuse to associate these words with massacres and murders.
We speak against using this phrase in this context. Those who do, they insult our religion and our religious values.
Those using these words while taking some unreligious, unspiritual, uncivilized actions are harming the religion.
Allahu Akbar is an expression of our faith.
One must not use these words for non-religion-related purposes in order to justify violence and terror.
To the question: “Do people say Allahu Akbar in church?” Archbishop Sebastia Theodosios replies:
For us, Allah is not an Islamic term. This is a word used in Arabic to indicate the Creator who’s made the world we are living in. So when we say Allah in our prayers we mean the Creator of this world.
In our prayers and pleas, in our Orthodox Christian religious ceremonies we use exactly this word. We say, glory be to Allah in all times. We say Allah a lot during our liturgy. It’s erroneous to think that the word Allah is only used by Muslims.
We the Arab Christians say Allah in our Arabic language as a way to identify and address the Creator in our prayers.
I have experienced this in Arabic-speaking Christian services. But I also experienced this in Christian services in Indonesia. The Bahasa Indonesia for ‘God’ is ‘Allah’.