What Is the True Name of the Most High?
Before we answer that, it would help to talk about language. There are about 7,000 languages spoken today. Since God is omniscient, he knows them all. Before the tower of Babel, thousands of years before Isa walked on earth, people spoke only one language (Genesis 11:1-9). No one knows what language that was. It might have died out then and there. Even if a descendant language exists, no speaker of it would understand its ancient ancestor. Languages change every generation. That makes literature several hundred years old difficult to read. Literature several thousand years old is impossible to understand today without special information.
What language does the Most High speak? Every language. What language did he speak before humans existed? No one knows. Maybe he spoke a near infinite number of languages. Maybe he didn't even speak like we understand the term. After all, the Almighty doesn't have a tongue, lips, teeth, and vocal cords like we do.
We can talk about and even debate this question. But more important than any pronunciation of any word is the actual meaning of the term God. There is only one Supreme Being. He is the creator of the world—all knowing and all powerful.
Even though people may not know Arabic or English or Chinese, Allah understands their language. He said the following about himself:
God does not view things the way men do. People look on the outward appearance, but the LORD looks at the heart. (1 Samuel 16:7, NET)
That goes for language, too. The Most High God is not concerned with teaching people how to pronounce foreign words, but how to live, act, think, and believe. Words are simple enough to mimic. Allah is concerned with deeper things, not the movements of our tongue and lips but the movements of our heart.
Allah* refers to the one and only God in Arabic. It's a beautiful name. Aramaic and Hebrew have similar words. But God revealed a different divine name to Prophet Musa, Yahweh (Exodus 3:14). Though distinct in sound, it also has a beautiful meaning: “the One who is.” Up until recently, a small group of people living in Southeast Asia had no alphabet. None of them wrote or read their own language. But they were not without a beautiful name for God: Mugbabaya—“the Ruler over all.” It's the meaning of a word that counts. Whatever the language and however we might pronounce the Creator's name, unless the word springs from a pure heart, what rolls off the lips means nothing to him. As the Scriptures say,
The LORD is near to all who call on him, to all who call on him in truth. (Zabur/Psalm 145:18, NIV)
* The etymology of Allah in Arabic is disputed. A very widespread theory is that it arose by fusing the Arabic article al with the generic word for God/god, ilah. On the other hand, many western scholars believe that the Syriac word for God, Alaha was taken into Arabic from Syriac neighbors and became Allah. Alaha itself was a later form of the Aramaic word for God/god used in the Holy Scriptures (Daniyal/Daniel 2:18, Mark 15:34) and closely related to the Hebrew words for God/god, i.e., el, eloah, and Elohim. In any case Allah is a word that both Arabic-speaking Muslims and Christians have used for more than a thousand years to refer to the one true God despite differences in understanding who he is.