drew,
the 2 Chronicles 36 passage is actually referancing two differant passages. Mainly the ones in Jeremiah as well as Leviticus.
Certainly true but how does that get around the problem I am pointing out -- i.e., that the Chronist holds a different interpretation of Jeremiah's 70 years as referring to the sabbath of the land according to the pattern of Leviticus 26, making them an ideal period of desolation?
My provisional understanding is that the OT contains at least three interpretations of the 70 years: (1) starting before the final fall of Jerusalem and ending with the fall of Babylon (Jeremiah, especially 29); (2) starting with the fall of Jerusalem but ending after the return from exile (Zechariah, Daniel); (3) beginning and ending with the desolation (sabbath) of the Judean land itself (2 Chronicles). I would add that (3) probably influences the ultimate redaction of the proto-Masoretic text of Jeremiah 25:11f, which seems to identify the 70 years to both (1) "the nations will serve the king of Babylon" and (3) "this land shall be in ruin".