What is the type of English used in the King James Bible called?

In the King James Version (KJV) of the Bible, there is a distinct type of English present (this passage from Job 1:7-12):

And the LORD said unto Satan, Whence comest thou? Then Satan answered the LORD, and said, From going to and fro in the earth, and from walking up and down in it.

8 And the LORD said unto Satan, Hast thou considered my servant Job, that there is none like him in the earth, a perfect and an upright man, one that feareth God, and escheweth evil?

9 Then Satan answered the LORD, and said, Doth Job fear God for nought?

10 Hast not thou made an hedge about him, and about his house, and about all that he hath on every side? thou hast blessed the work of his hands, and his substance is increased in the land.

11 But put forth thine hand now, and touch all that he hath, and he will curse thee to thy face.

12 And the LORD said unto Satan, Behold, all that he hath is in thy power; only upon himself put not forth thine hand. So Satan went forth from the presence of the LORD.

(source)

There are specific words used from (old? middle?) English, like unto, thou, whence, comest, fro, hast, and the ending certain words with -eth, like feareth, and escheweth.

There are modern writings that tend to imitate this style of writing, as an example, this "Ten Commandments of Writing an IMAP client":

1. Thou shalt not assume that it is alright to open multiple IMAP sessions selected on the same mailbox simultaneously, lest thou face the righteous wrath of mail stores that doth not permit such access. Instead, thou shalt labor mightily, even unto having to use thy brain to thinketh the matter through, such that thy client use existing sessions that are already open.

Which brings me to my question: I'd like to critique this writing style and refer to it, but I don't know what it's called. What is the type of English used in the KJV called, and (if it's the same — or even if it isn't), what's the writing style used to parrot the KJV writing style called? It can be referred to in a single word or a phrase — I'm just interested in making sure I use the right terminology in referring to it.

The KJV is written in Early Modern English (not Middle or Old English).

Styles that imitate this use archaic English, which the Oxford English Dictionary describes as:

Belonging to an earlier period, no longer in common use, though still retained either by individuals, or generally, for special purposes, poetical, liturgical, etc. Thus the pronunciation obleege is archaic in the first case; the pronoun thou in the second.

Archaic is how dictionaries like Lexico (also by Oxford) describe unto and shalt.

(You’ll also see some words marked obsolete in the dictionary. The difference between archaic and obsolete is that obsolete words aren’t used anymore.)

Supplementary to Ray Butterworth's answer:

If you speak of this as the 'Biblical' style, and the modern parodies as 'Mock-Biblical', people will understand you.

As @Laurel says, the underlying English dialect is Early Modern English; but you need to realize as well that the Authorized Version is a translation which seeks to reflect both the various styles employed in the Hebrew and Greek originals and a literary tradition of Biblical translation stretching back two hundred years in English (and beyond that to the 4th-century Latin Vulgate). The 'Biblical' style was already established and familiar to its readers when the AV was first published: both the AV and its Catholic competitor the Douai-Rheims translation were stylistically based on the earlier work of Tyndale (1525), which hearkens back to Wycliffe's Middle English translations.

The theological authority of the AV carried over to its style, which dominated religious translation and expression in English for the next three centuries. The style was followed not only by translators of the Hebrew-Greek scriptures and works from other religious traditions such as the Quran and the Upanishads, but also by new works claiming religious authority, such as Joseph Smith's Book of Mormon and Aleister Crowley's Thelemist texts.

The Biblical style is so widespread that it's immediately recognized by virtually all English speakers, and is thus eminently suited to parody.

The King James Bible was written in the same place and at the same time as Shakespeare's plays, but the styles of these two works are very different.

Shakespearean style requires a much larger vocabulary to understand and uses much more complicated sentence structure. The Biblical style is mostly simple words in easy to follow sentences. Shakespeare's works contain 31,534 different words, while the Old Testament and New Testament contain only 10,867 and 6,063 different words each (and a large number of those are proper nouns naming specific people and places).

So the style you refer to is not simply because of where and when it was written. Referring to it as "Elizabethan" or "Early Modern English" is misleading.

I'd simply call it "biblical" style.

And I'd say the given quotation is written in "mock biblical" style, especially since it is such a poor attempt at copying biblical style:

• Until recently "alright" didn't even exist as a word.
• "doth" is third person singular, but here it is used with a plural subject.
• many verbs appear in modern form and aren't conjugated with "-t" (2^nd person) or "-th" (3^rd person) suffixes.

How about Elizabethan?

Elizabeth I (7 September 1533 – 24 March 1603) was Queen of England and Ireland from 17 November 1558 until her death on 24 March 1603. Sometimes called the Virgin Queen, Gloriana or Good Queen Bess, Elizabeth was the last of the five monarchs of the House of Tudor.

Just for fun, check out this article for ways in which you can become conversant in Elizabethan English. Here's a fairly long excerpt:

2Sounding Funny Is Fun! (No, really, it's actually a blast)The biggest changes from our modern tongue come in the vowels. You remember kindergarten, right? A-E-I-O-U and Sometimes Y? In the English language, the vowels are the most flexible sounds, bending and morphing around the consonants they are framed with. In Elizabethan English, the vowels are the sounds that are the most different from our modern accent. Some pronunciations stay the same (we love those!) and some change.

Let's start at the top. We'll give the letter - or the sound - and examples of how that letter sounds in our modern accent, then explain the differences: Vowels A - cat, hat This version of the a, the short a, is basically the same. It is drawn out a bit, held onto just a little... caaat, haaat. A - father, walking This short a changes to a flat a like in "pant". So father rhymes with rather, walk sounds like whack. A - take, make, stable This long a becomes an eh sound. So take sounds like tek, make sounds like mek, stable like steble. Funny huh? E - head, dead The eh sound of these words becomes an ay or ai sound. So head and dead rhyme with braid. I and Y - lie, die, my, by The long i sound becomes an uh-ee sound. If you say my really really slowly, it sounds like m-ah-ee... instead, we're going to say m-uh-ee. This isn't oi like Yiddish! Lie sounds like l-uh-ee, die sounds like d-uh-ee, my sounds like m-uh-ee, by sounds like b-uh-ee.I - hit The short i stays the same (yay!) and rhymes with it. O - come This one becomes much darker and rounder... almost au sound.

You can almost throw in a uh sound too. So come becomes coom, of becomes uh-oov.U - cup, cut The short u sound combines with the "oo" sound, like "coop". If the short u and the oo sound had babies, that's what the short u should sound like. So cup becomes coop, cutbecomes coot. Let's add an R 3The r in Elizabethan English is more exaggerated, a hard r, but isn't quite the pirate "ARRRR!", or a rolled r. It's a consonant you can really chew on... never be afraid to lean on it and draw it out a little. ER - mercy This sound rhymes with air, and the r is emphasized. Mercy becomes maircy, terse sounds like tairce, curse becomes cairse. OR - Lord This takes on a very round mouth shape and the short o is almost an "oo" sound.

Lord becomes loord, ford becomes foord. The Diphthong! Diphthongs are not what happens when women wearing low rise jeans and thong underoos sit down. Rather, they are vowel combinations... In modern English, we usually shorten diphthongs to one quick sound... Elizabethan English usually uses both letters. After all, why would you put both in if they weren’t to be used? There is one exception, but that will be pointed out below. AI - fair In this case, both letters are pronounced. The a is a short a and the i is like the Elizabethan i. The r is hard, and a little exaggerated (but not rolled or the pirate rrrrrr). So "fair" becomes fah-ay-err. AY - say Pronounce both letters - so saay-ee. EI - either This is the diphthong exception. It becomes an "ay" sound, so either becomes ayther. OU - mouse Pronounce both letters, so mouse becomes muh-oose. Not "moose"... round out the ou sound and make it darker. House becomes huh-oose. OW - brown This is very similar to the OU - the W is afer all, a double u.Brown becomes bruh-oon. . . ..

Most of the consonants stay the same. There are a few, however, that do change. C - precious Modern English has turned the "cious" letter combination into "shun". We're going to turn the c into an s, and then say the rest of the letters. Precious sounds like preh-see-uhs, musician sounds like myu-zih-see-un. G and V - speaking, ever 4The G that appears at the ends of words can be dropped. Likewise, the V in the middle of words can often be dropped as well. This is especially appropriate for lower class characters. Speaking becomes speakin', listening becomes listenin', ever becomes e'er, evenbecomes e'en. Lower classes might even drop the v in heaven, making hea'en.H - hoop Every H is spoken (think Pygmalion, which was retold as My Fair Lady). Hoop is never oop, but always spoken with the letter H. Hand, heavy, hark, all use the H. K - knight

Modern English has turned the leading K in words like knight and knife silent. At this time, it was sometimes spoken, especially by the lower classes. Knight becomes kuh-night, knife becomes kuh-nife. R - art Remember the R from "lord"? Same deal... lean on it a little! Chew on it and enjoy it... R's are very fun to say. Arrrt! (Ok, that's a little piratey) S - compassion The double S, and sometimes single S, has become a sh sound in modern times. However, back in the day it was spoken as a hard s... instead of compashun, we're going to say comp-ah-see-ion, and instead of surely pronounced serly, it becomes soor-ly. T - righteous Like the S, sometimes a T isn't a T - it's a CH. Nowadays we say richus, but in Elizabethan speak we'd say each letter and get ri-tee-ous. Pastures goes from paschurs to pas-toors.