Codex Sinaiticus is generally dated to the fourth century, and sometimes more precisely to the middle of that century. This is based on study of the handwriting, known as palaeographical analysis. Only one other nearly complete manuscript of the Christian Bible – Codex Vaticanus (kept in the Vatican Library in Rome) – is of a similarly early date. The only manuscripts of Christian scripture that are definitely of an earlier date than Codex Sinaiticus contain small portions of the text of the Bible.
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