This verse shows that Manasseh not only sinned in his relationship with the people, by which the Judean people did what the Lord finds very wrong; but he also sinned in his relationship with the people by behaving like a worldly tyrant. The king of the Lord, seated in the city of peace, must be a Messianic ruler. That means that he should show the reign of the heavenly King as much as possible. Subjects ought to feel safe with the king. Manasseh shed a lot of innocent blood, it says. Among those who were murdered were undoubtedly those who did want to live according to the Word of the Lord or those who were pushed to worship idols. One can think of the prophets who called Manasseh out on his sins. In 2 Kings 24:3–4 the Lord also mentions how terrible the bloodshed was. The beginning of the subjugation of Judah to Babylonia is mentioned here in 2 Kings 24, and it is telling that as separate reason it is noted that the subjugation happened especially due to the innocent blood that Manasseh had shed. All of 2 Kings 24:4 is about the seriousness of that blood shedding.
We see two things in this verse:
1. When someone silences the Word of the Lord (by, for example, killing his prophets), then the Lord seriously reckons the culprit.
2. Dictators and tyrannical regimes which despise the lives of their subjects will not escape their due punishment.
16 Moreover, Manasseh shed very much innocent blood, till he had filled Jerusalem from one end to another, besides the sin that he made Judah to sin so that they did what was evil in the sight of the LORD.