"Allah, the paramount deity of pagan Arabia, was the target of worship in varying degrees of intensity from the southernmost tip of Arabia to the Mediterranean. To the Babylonians he was "Il" (god); to the Canaanites, and later the Israelites, he was "El"; the South Arabians worshiped him as "Ilah," and the Bedouins as "al-Ilah" (the deity). With Muhammad he becomes, God of the Worlds, of all believers, the one and only who admits of no associates or consorts in the worship of Him. Judaic and Christian concepts of God abetted the transformation of Allah from a pagan deity to the God of all monotheists. There is no reason, therefore, to accept the idea that "Allah" passed to the Muslims from Christians and Jews." [Caesar E. Farah, Ph.D., Islam [Barron's Educational Series, 2000, sixth edition paperback] p. 28]
This is entirely correct. Al-Lah, El-Lah, i-Lah or the 'one', the 'Lord', has nothing in common with Judeo-Christian ideals including conceptions of 'god'. Islam is a clumsy, ahistorical and overall an ignorant attempt to conflate two different strands of metaphysical theology. Pagan Arabian practices, fused with celestial worship including that of the sun goddess [Allat] and the moon [Ba'al or Hub'al], have no corollary or similarity with the belief and ritual systems in either Judaism or the offshoot philosophy of Christianity. To say that Islam is the 'same' as the other 2 monotheisms would be as absurd as claiming that the Hittite Sky God, or the Grecian Zeus were both the 'same' belief systems as the 2 Hebrew inspired constructs. Nonsense.
Former Muslim and now atheist Ibn Warraq [not his real name of course since the moon cult of tolerance kills apostates.....] describes in concrete terms the moon worship embedded in the veneration of Allah:
Allah as a name
...Islam owes the term "Allah" to the heathen Arabs. We have evidence that it entered into numerous personal names in Northern Arabia and among the Nabatians. It occurs among the Arabs of later times, in theophorus names and on its own. Wellhausen also cites pre-Islamic literature where Allah is mentioned as a great deity. We also have the testimony of the Koran itself where He is recognized as a giver of rain, a creator, and so on; the Meccans only crime was to worship other gods beside Him. Eventually Allah was only applied to the Supreme Deity. "In any case it is an extremely important fact that Muhammad did not find it necessary to introduce an altogether novel deity, but contented himself with ridding the heathen Allah of his companions subjecting him to a kind of dogmatic purification ... Had he not been accustomed from his youth to the idea of Allah as the Supreme God, in particular of Mecca, it may well be doubted whether he would ever have come forward as the preacher of Monotheism."
Hail Hubal – Muhammad did
The Black Stone itself is evidently a meteorite and undoubtedly owes its reputation to the fact it fell from the "heavens." ....Hubal was worshipped at Mecca, and his idol in red cornelian was erected inside the Kaaba, above the dry well into which one threw votive offerings. It is very probable that Hubal had a human form. Hubal's position next to the Black Stone suggests there is some connection between the two. ....Wellhausen also points out that God is called Lord of the Kaaba, and Lord of the territory of Mecca in the Koran. The Prophet rallied against the homage rendered at the Kaaba to the goddesses al-Lat, Manat, and al-Uzza, whom the pagan Arabs called the daughters of God, but Muhammad stopped short of attacking the cult of Hubal. From this Wellhausen concludes that Hubal is no other than Allah, the "god" of the Meccans. When the Meccans defeated the Prophet near Medina, their leader is said to have shouted, "Hurrah for Hubal."
The Romans mention it:
“...Clement of Alexandria, writing ca. 190, mentioned that "the Arabs worship stone," alluding to the black stone of Dusares at Petra. Maximus Tyrius writing in the second century says, "The Arabians pay homage to I know not what god, which they represent by a quadrangular stone": he alludes to the Kaaba that contains the Black Stone. Its great antiquity is also attested by the fact that ancient Persians claim that Mahabad and his successors left the Black Stone in the Kaaba, along with relics and images, and the stone was an emblem of Saturn ...
Astral worship:
...It is unquestionable that the Arabs "at a comparatively late period worshipped the sun and other heavenly bodies." The constellation of the Pleiades, which was supposed to bestow rain, appears as a deity. There was the cult of the planet Venus which was revered as a great goddess under the name of al-Uzza.
We know from the frequency of theophorus names that the sun (Shams) was worshiped. Shams was the titular goddess of several tribes honored with a sanctuary and an idol. Snouck Hurgronje sees a solar rite in the ceremony of "wukut" ...
The goddess al-Lat is also sometimes identified with the solar divinity...The worship of the moon is also attested to by proper names of people such as Hilal, a crescent, Qamar, a moon, and so on.
[Ibn Warraq, Why I Am Not A Muslim [Prometheus Books, Amherst NY, 1995], pp. 39-40, 42]
This El-Lah thing was simply the idol inter-pares, the first pagan deity amongst the host of 360 such idols. Moslems vociferously protest that Hub'Allah is not Allah. Their protestations are moot. The word i-Lah refers to the one. If the 'one' was Allat then it is the Sun Goddess they worshipped. If the 'one' was Hub'Al, the moon deity. If the 'one' meant something else than that entity was or is 'supreme'. There is no doubt that the pre-Islamic Arab world venerated astral deities. We can quibble about who exactly 'Allah' might be. There is little doubt at least in my mind, that Allah is Hub'Allah or the male [some say female] Assyro-Babylonian moon deity. The great preponderance of evidence supports that conclusion. But even if we don't apply Occam's razor to solving the mystery of what Allah is, there can be little doubt, that any serious study of the Koran, of Muhammad, or of Arab history reveals the obvious – that Allah has nothing whatsoever to do with the Judeo-Christian ideal of what a 'god' is suppose to be.