LONDON - THE surviving pages of the world's oldest Christian Bible have been reunited - digitally.

The early work known as the Codex Sinaiticus has been housed in four separate locations across the world for more than 150 years.

But starting on Monday, it became available for perusal on the Web at www.codexsinaiticus.org so scholars and other readers can get a closer look at what the British Library calls a 'unique treasure.'

'(The book) offers a window into the development of early Christianity and firsthand evidence of how the text of the Bible was transmitted from generation to generation,' said Scot McKendrick, head of Western manuscripts at the British Library.

As it survives today, Codex Sinaiticus comprises just over 400 large leaves of prepared animal skin, each of which measures 380mm by 345mm.

It is the oldest book that contains a complete New Testament and is only missing parts of the Old Testament and the Apocrypha.

The 4th-century book, written in Greek, has been digitally reunited in a project involving groups from Britain, Germany, Russia and Egypt, which each possessed parts of the 1,600-year-old manuscript.

They worked together to publish new research into the history of the Codex and transcribed 650,000 words over a four-year period.

The Codex was both a key Christian text and 'a landmark in the history of the book, as it is arguably the oldest large-bound book to have survived,' Mr McKendrick said.

Codex Sinaiticus, which loosely translated means 'the book from Sinai,' was discovered at the Monastery of Saint Catherine at Mount Sinai by German Bible scholar Constantine Tischendorf in the mid-19th century.

Much of it eventually wound up in Russia - just how exactly the British Library won't say, citing lingering sensitivity over the circumstances surrounding its removal from the monastery. -- AP