Even when the KJV was written it read a bit funny and faux archaic. But by and by some of the snappier phrases got picked up, a couple of my favourite that many people have no idea come from the Bible are "apple of my eye" and "skin of my teeth." The KJV is worth reading, at least once, as literature, but as scripture it was suspect from the start and for most of us now is of definate limited use due to the way the English language has changed over the 4 centuries since. But anyway some chap is blogging through all the phrases that have made their merry way into English usage and you may want to check him out, after I tip my hat to Richard Walker.
Giles Fraser's excellent Guardian post is also worth a read. A snippet:
Except, of course, that is precisely what the KJB was: an attempt by the Church of England to control the religious and cultural agenda. A team of academics was established in 1604 to translate the Bible in such a way that it bolstered the authority of the established church. James I gave the specific instruction that the translation must toe the official line on the importance of bishops. The Greek word ekklesia was to be translated as "church", rather than "congregation" or "assembly" – the translators thus giving the impression that the Bible proposes a top-down form of ecclesiastical authority.
Unfortunately even modern translations still often continue the tradition of translations that support the status quo, those in power and the peculiar pruderies of dusty old scholars.