Arab Christians and Jews said Allah before Islam existed, and many still do
Allah is simply the Arabic word for God. Pre-Islamic Arab Christians wrote it in inscriptions and poems and reportedly shouted it as a battle cry, and today Arabic-speaking Jews and Christians, Maltese and Indonesian Christians, and Baha'is all use it. Its roots run back to the Semitic god name El.
Most scholars, including the classical Arab philologists who debated it at length, derive the word from a contraction of al-, the Arabic definite article, and ilah, meaning deity, giving the god. The same pattern produced Allat from al-ilat. Its relatives span the Semitic languages: Aramaic Elaha, Syriac Alaha, Hebrew Eloah, Akkadian ilum and Ugaritic ilu. Ilah itself began as an epithet of the West Semitic creator god Ilu, the Ugaritic form of El. A minority view treats Allah as borrowed from Syriac, though adaptation to Arabic sound patterns is thought more likely.
Before Islam, Allah was the highest god in an Arabian pantheon, worshipped alongside lesser deities. Now the word expresses the uniqueness of one God. The historian Marshall Hodgson suggests some Arab Christians made pilgrimages to the Kaaba, then a pagan shrine, to honour Allah as creator. A Christian martyrion inscription from 512 opens by invoking al-ilah in both Arabic and Aramaic. A proposed reference at a church ruin in Umm el-Jimal, Jordan, was later rejected when scholars retranslated the text in the 1980s.
Tenth-century sources add colour. Irfan Shahid, drawing on the Kitab al-Aghani, notes that Christian Arabs reportedly rallied each other with a cry calling themselves slaves of Allah, and Ghassanid and Tanukhid poets in Syria and northern Arabia are said to have named Allah in their verse.
Within Islam, Allah is regarded as God's most distinctive proper name, called the Word of Majesty. Muslim scholars have resisted linking it to the names of other gods. Grammarians of the Basra school saw it as a spontaneous coinage or a form from a root suggesting lofty or hidden, while others tied it to a word for the object of mystery, since God lies beyond human understanding. Early theologians even argued over whether divine names were created or eternal, with Ibn Hanbal rejecting the created view.
Source: Allah