Rick Brown wrote an article about the origin of the name ALLAH. As this theme keeps coming up among western Christians and in Malaysia, here this good article by Rick Brown:
In talking with Muslims, it is essential to understand and affirm their names for God. In most languages spoken by Muslims, the term allâh is at least one of their names for God. Dudley Woodberry (1996a: 173) has pointed out that the name allâh “is of Christian Syriac origin and was in use long before Muhammad’s time.” Syriac-speaking Christians have always believed this, and scholars like Arthur Jeffrey (1938: 66) have noted this as well. But violent acts perpetrated by some militant Islamists in the name of allâh have led many people in the West to conclude that allâh must be someone besides God.