The book of Jeremiah was originally written in Hebrew. What we read as the book of Jeremiah in our English Bibles is mostly translated from this Hebrew version. However, the Old Testament – including Jeremiah – was translated into common Greek about 250 years before Christ. Thus Jeremiah in the Septuagint is in Greek.
This translation of the Old Testament is called the “Septuagint” because history says that the translation was made by seventy men (or maybe 72!) and “septuagint” means seventy in Latin. This also is the source of the abbreviation “LXX” – seventy in Roman numerals – which is commonly used for the Septuagint.
As you would expect from a translation, the Hebrew and Septuagint (LXX) versions of Jeremiah are mostly very similar but they are also different in some significant ways that might surprise you.
Overall, the Septuagint version shows signs that someone tried to put parts of the book in more chronological order – particularly the last few chapters of prophecy (Jeremiah 46-51). These were probably delivered in or before the 4th year of Jehoiakim, and the LXX inserts them in the middle of chapter 25. Thus to find a chapter in the LXX from chapter 26 onward, just add 7. There are a few extra changes also, but this is the basic picture.
In a little more detail, here are the differences in the arrangement of these chapters:
From the web page referred to below, we can get a list of the significant (larger) omissions from the LXX translation of Jeremiah. Some of them are interesting to note:
|Jeremiah 8:10-12||quite similar to Jeremiah 6:12-15|
|Jeremiah 10:6-8,10||speaks of God’s greatness|
|Jeremiah 11:7-8||God’s command for obedience ignored|
|Jeremiah 17:1-4||Jeremiah 17:3-4 similar to Jeremiah 15:13-14|
|Jeremiah 29:16-20||Jeremiah 29:16-18 similar to Jeremiah 24:8-10, Jeremiah 29:19 to Jeremiah 25:4 and Jeremiah 29:20b to Jeremiah 24:5b|
|Jeremiah 30:10-11||similar to Jeremiah 46:27-28|
|Jeremiah 33:14-26||Jeremiah 33:14-16 is similar to Jeremiah 23:4-6 and Jeremiah 33:25-26 to Jeremiah 31:35-36|
|Jeremiah 39:4-13||Jeremiah 39:4-7 similar to 2 Kings 25:4-7|
|Jeremiah 48:45-46||judgement on Moab|
|Jeremiah 51:44d-49a||judgement on Babylon (some similarity with other verses in Jeremiah 51)|
|Jeremiah 52:2-3||very similar to 2 Kings 24:19-20|
|Jeremiah 52:27c-30||Jeremiah 52:27c very similar to 2 Kings 25:21|
Most of the passages left out of the LXX are passages repeated elsewhere in Jeremiah, or are very similar to other passages in Jeremiah. Maybe the translators at that time followed the same train of thought as many translators today who think that if the passage is duplicated, it must be the result of a copying error or “enhancement”. However, if we accept God as the author of the Bible, repeated text should not be a surprise, and definitely not an automatic reason for exclusion. Just look at Isaiah 2:2-4 and Micah 4:1-3. They are almost identical and were even written at a very similar time. Maybe repetition should make us sit up and take notice!
While the differences, particularly the omissions, are interesting to think about, the massive majority of the Septuagint version of Jeremiah is very similar to the Hebrew version. Although the two translations became separate documents so long ago and have been copied hundreds or thousands of times since, the differences between them are very small, particularly given the size of the book of Jeremiah which is the longest book in the Bible.
Yet again, this gives us reason to be confident that the Bible has been accurately copied through the twenty-six centuries that have passed since the book of Jeremiah was written.
 For more information about the Septuagint, see Wikipedia (https://en.wikipedia.org/wiki/Septuagint).
 A summary of the differences between the Hebrew and Greek versions of Jeremiah is shown here: https://www.ccel.org/bible/brenton/Jeremiah/appendix.html.
 By word count in Hebrew (http://overviewbible.com/word-counts-books-of-bible/).