God did not forgive the nation of Judah once.
“However, the LORD did not turn from the fierceness of His great wrath with which His anger burned against Judah, because of all the provocations with which Manasseh had provoked Him. And the LORD said, “I will remove Judah also from My sight, as I have removed Israel. And I will cast off Jerusalem, this city which I have chosen, and the temple (house) of which I said, ‘My name shall be there.’”
“Surely at the command (mouth) of the LORD it came upon Judah, to remove them from His sight because of the sins of Manasseh, according to all that he had done, and also for the innocent blood which he shed, for he filled Jerusalem with innocent blood; AND THE LORD WOULD NOT FORGIVE.” (All caps mine) 2 Kings 23: 26 & 27 and 24: 3 & 4
First the king repented and Josiah his grandson would lead the greatest revival under a king but God still judged Judah and that happened when Josiah’s son returned to sacrificing children to a false god. That judgment was fulfilled by Nebachudnezzar of Babylon for 70 years. Lamentations was written. God did restore the nation but He could not NOT avenge the death of the innocent. The world is in big trouble.
Thanks for the scriptures, will devote some time and study them more carefully.