“In the third year of the reign of Jehoiakim king of Judah.” At first blush, Daniel 1:1 seems to contradict Jeremiah 25:1-9. Here in Daniel 1, in the third year of Jehoiakim of Judah, Nebuchadnezzar had already attacked Judah and taken captives, and Daniel was one of them (Dan. 1:2-6). In contrast, Jeremiah says it was Jehoiakim’s fourth year and Nebuchadnezzar had not even attacked yet.
Actually, both Jeremiah and Daniel are accurate. What the reader must know is that when dates are given in the Bible, they are usually, but not always, given from the point of the one who is writing. Jeremiah, living in Judah, was dated using Judean Nisan year (the Judean year started in Nisan in Judah, just as our modern year starts in January). In contrast, Daniel, a captive in Babylon, was using Tishri dating, starting in the month Tishri, which was 6 months different (in this case, later) than Nisan. So when Nebuchadnezzar started his first year, it was the third year according to Daniel’s Tishri year dating, but it was already the fourth year of Jehoiakim according to Jeremiah’s Judean dating system (cp. Edwin Thiele, The Mysterious Numbers of the Hebrew Kings, Zondervan Pub. Co., 1983, p. 183).