Is Allah in the Quran the same God as YHWH in the Bible? God in the Bible is not the same character or personality as God in the Quran, and there are significant theological contradictions between them. However, Arab Christians call God Allah, not because they believe Islam has the same God theologically, but because Allah means the (one) God in Arabic. The Arabic-descended Maltese language of Malta, whose population is almost entirely Roman Catholic, uses Alla for “God”. The Aramaic word for “God” in the language of Assyrian Christians is Elaha, or Alaha. A German speaker wouldn’t say ‘God’ either; they would say ‘Gott,’ which is where the English word ‘God’ originates, as English is a Germanic language. Nor would a Spanish speaker say ‘God,’ they would say ‘Dios’ because that is the word for God in Spanish. They are merely the words used to classify a deity, similar to how words like El-Shaddai or Adonai (meaning “the Lord”) in Hebrew function as titles for God, or God Almighty. However, these are not necessarily the name of God, such as YHWH. Likewise, the New Testament is translated from Greek, which uses the word Theos (Θεός) for God. Paul didn’t make Greeks stop saying Theos and switch to Adonia, so I don’t believe Arab Christians must use something other than Allah.