The fall of the Kingdom of Judah and the profound suffering of its people were not the result of shifting political alliances or the overwhelming military strength of foreign empires. Instead, the tragic fate of the nation was the direct execution of a divine decree. The foreign invasions that ravaged the land did not succeed because these nations possessed superior power. Rather, everything unfolded according to the explicit order and decree of God [רש״י, מצודת דוד]. The ultimate purpose of this harsh judgment was to remove the people of Judah from His presence entirely [ביאור שטיינזלץ].
The root cause of this punishment is traced back to the historical sins of King Manasseh, which raises a fundamental question about divine justice. It seems difficult to understand why a later generation would suffer for the crimes of a ruler who lived long before them.
One perspective explains that the severe decree to destroy Jerusalem was actually sealed by God through His prophets during Manasseh's reign. If not for the overwhelming magnitude of Manasseh's sins, God might have forgiven the wrongdoers who followed him. While the merit of the righteous King Josiah temporarily delayed the punishment and extended God's patience, the wickedness of the current king, Jehoiakim, brought that patience to an end. God chose to wait no longer, and the ancient decree was finally put into action [רד״ק, אברבנאל בשם המפרשים].
Another approach resolves this issue by placing the blame squarely on the generation of the destruction itself. According to this view, the people were not punished for the historical sins of Manasseh, but because they actively continued his evil practices. Although Manasseh repented at the end of his life, the people of Judah did not join him in his return to God. Instead, they kept worshipping idols and shedding innocent blood exactly as he had originally taught them. Therefore, the nation was judged and punished for their own ongoing, present corruption, having mirrored the terrible actions of their former king [אברבנאל, מצודת דוד].