2 Chronicles 36:21

to fulfill the word of the Lord by the mouth of Jeremiah, until the land had enjoyed her Sabbaths; the Sabbatic years, as seasons of rest for all classes of people and for the land itself having been ignored for centuries, the Lord was now giving the land lest, Leviticus 26:34; for as long as she lay desolate, she kept Sabbath, for a mere handful of people remained in the land after Nebuchadnezzar's campaign, and many of these went down into Egypt in the course of time, to fulfil threescore and ten years. It seems that no attempt was made to colonize the land in the interval, and that Judah was actually desolate for seventy years.