Even in their earliest days, important differences existed between the Hebrew text and the Greek Septuagint because the latter's increasing popularity led to thousands of handwritten copies where scribes multiplied mistakes. Over time, marginal notes and footnotes were accidentally added into the body of the text, causing the Greek and Hebrew Bibles to diverge more widely through a process of continual corruption.
The Jewish community regarded the Septuagint only as a translation of the original Hebrew, never as an independent or authoritative scripture.
Paul's Christianity had a universal ambition; it aspired to bring salvation to the world.
Christianity had to reject the Hebrew representation of scripture, written in the obscure, provincial tongue only the Jews spoke, and to announce the miraculous new revelation of Septuagint, the eternal bible reincarnated in a language that everyone understood.
In Exodus 3:14, God reveals His divine name to Moses as 'I AM WHO I AM' (Hebrew: Ehyeh Asher Ehyeh). In the Greek Old Testament (Septuagint), this is rendered as 'Ego eimi ho on' ('I am the Being'). Scholars note that Jesus' absolute uses of 'Ego Eimi' echo both Exodus 3:14 and the self-declarations of Yahweh found throughout the book of Isaiah.
In the Septuagint translation of Isaiah (e.g., Isaiah 41:4, 43:10, and 45:18), God repeatedly declares 'Ego Eimi' to assert that He alone is Yahweh and there is no other Savior. New Testament scholars recognize that John's Jesus adopts this precise phrasing from Isaiah to show that the long-awaited salvation and physical embodiment of Yahweh is now present in Christ.