Charles Ellicott Commentary 2 Chronicles 25:27

"Now from the time that Amaziah did turn away from following Jehovah they made a conspiracy against him in Jerusalem; and he fled to Lachish: but they sent after him to Lachish, and slew him there." — 2 Chronicles 25:27 (ASV)

Now after the time that Amaziah did turn away from following the Lord. —This clause is added by the chronicler, not so much with the aim of assigning a date, as of asserting the real connection between Amaziah’s defection from Jehovah, and the calamities that overtook him. Essentially he calls attention to the fulfilment of the prophecy of 2 Chronicles 25:16.