A title like The Cambridge Handbook of Language Policy carries a reassuring message of solid reliability. The first chapter I happened to open it to, however, rather belies this reputation: "Language policy and religion", by Christina Bratt Paulston and Jonathan M. Watt. I'm sure its authors have plenty of expertise in, respectively, sociolinguistics and Biblical Studies. Unfortunately, they decided to pick a case study to which their expertise very clearly does not extend: "Islam and Qur'anic Arabic". This produced some rather serious misapprehensions, of which I'll explain the worst here for the benefit of any readers of the article.
"Presumably the existence of Allah and Jehovah are considered mutually exclusive by their believers" (p. 340) is self-evidently absurd. Muslims necessarily believe that they worship the God worshipped by Abraham and Moses, and that there is no other God. The Qur'an instructs Muslims to tell Christians that "our God and your God is one", and Arabic-language Bibles or Torahs call "Jehovah" Allah. (Malaysia's bizarre and unjust recent court decision to ban non-Muslims there from calling God "Allah" might suggest otherwise, but as far as I can tell, no one involved is claiming that Jehovah is a different entity from Allah; rather – as far as I can reconstruct their tortured reasoning from the brief sound-bites in the news – they're claiming that, at least in Malay, the word "Allah" ought to be exclusive to Muslims.)
"The insistence that the sacred book was transmitted from heaven in this language, and none other, appears never to have been challenged from within this religion" (p. 341). Obviously, the Qur'ān got here in the language that it's written in (unless you subscribe to the philologically untenable fantasies of Luxenberg). But the Qur'ān is not the only book which Islam acknowledges as a divine revelation - just the last, and the only one considered to have been preserved in its original form up to the present. And the Qur'an is rather explicit regarding the language of previous prophets: "We have not sent any Messenger except with the language of his people so he can make things clear to them". As the great 11th-century jurist and writer Ibn Ḥazm put it: "This means that Allah’s words and revelations were sent down in every language. He sent the Torah, the Gospel, and the Psalms. He spoke to Moses in Hebrew. He sent the Scrolls to Abraham in Syriac. Therefore, languages are equal in this regard."
"[The Qur'an] is an unflinching sequence of pronouncements, blessings, commendations, condemnations and exhortations: absent are narrative tales, devotional songs and meandering reflections" (p. 346). I can't see how this sentence could have been written by anyone who had actually read the Qur'ān, which is full of narrative tales and includes a good deal of reflection. (Not singing, of course, but anyone who has heard the Qur'ān recited will understand how it might take the place of "devotional songs".)
"The very name of Islam's book means 'that which is recited' or 'the collected things', and, as Cooper (1985: 55) notes, it shows a preference for the Qurayish (sic) tribal dialect" (p. 342): Qur'an could be rendered as "recitation", but has nothing to do with "the collected things", much less with the dialect of Quraysh.
"formal public readers of the Qur'an are clerics, never laymen" (p. 343): actually, in Islam there's no hard and fast dividing line between "clerics" and "laymen" in the first place. Any Muslim can and often does lead public prayers (which include the recitation of parts of the Qur'ān). Admittedly, the more public the setting, the stronger the preference for people who have memorised the whole book and studied its meaning and pronunciation in detail – I suppose you might call them "clerics", if you want to ignore the fact that they don't necessarily have any formal role at the mosque, and as likely as not have day jobs.
The presence of such errors, and more pervasively of strange gaps and perspective problems, become more understandable when you take a look at the references. In the whole section, only six works are cited on Islam and Qur'anic Arabic, apart from translations of the Qur'ān: Abdalati 1975 (Islam in Focus, an introduction to Islam for the general reader); Cooper 1985 (Ishmael My Brother, an elementary introduction to Islam for Christians); W. M. Watt 1968 (What is Islam?, an academic introduction to Islam); Ibn Warraq 1995 (Why I Am Not A Muslim); Rippin and Knappert 1990 (Textual Sources for the Study of Islam); and Speight 1989 (God is One, another introduction to Islam for Christians). That makes four beginners' introductions, one polemic, and one scholarly sourcebook. This is a reference list fit for a first-year undergrad's essay, not a published academic article.
If you haven't read this article, you're not missing anything. But if you find it on a reading list, consider forwarding this to whoever assigned you it.