But Manasseh repented ...
Chronicles goes on to report that Manasseh then truly repented of his sins. "The Lord was moved by his entreaty and listened to his plea," (2 Chron. 33:13), and Manasseh was thus restored to his throne. He then demonstrated the genuineness of his change of heart by devoting himself to measures of defense, administration, and monotheistic religious reform.
He got rid of the foreign gods and removed the image from the temple of the Lord, as well as all the altars he had built on the temple hill and in Jerusalem; and he threw them out of the city. Then he restored the altar of the Lord and sacrificed fellowship offerings and thank offerings on it, and told Judah to serve the Lord, the God of Israel. The people, however, continued to sacrifice at the high places, but only to the Lord their God (2 Chron. 33:15-17).
The deuterocanonical Prayer of Manasseh purports to be the penitential prayer spoken by Manasseh, in which he declares:
You, O Lord, God of the righteous, have not given repentance for the righteous, for Abraham and Isaac and Jacob, who had not sinned against You, but You have given repentance for me, the sinner. For I have sinned more than the number of sand of the sea… I have set up abominations and multiplied provocations. And now I bend the knee of my heart, begging for Your clemency. I have sinned, O Lord, I have sinned; and I know my lawless deeds. I am asking, begging You: Forgive me, O Lord, forgive me! Do not destroy me with my lawless deeds, nor for all ages keep angry with me, nor condemn me to the depths of the earth, for You, O Lord, are the God of those who repent.
Such accounts, however, are difficult to square with the writing of the prophet Jeremiah who insisted that the crying need in the days of Josiah, Manasseh's successor after the two-year reign of Amon, was religious reform. Jeremiah also declared that Manasseh's sins had yet to be expiated: "I will make (my people) abhorrent to all the kingdoms of the earth because of what Manasseh son of Hezekiah king of Judah did in Jerusalem" (Jer. 15:4).
After his nation's longest reign, Manasseh died and was buried at Uzza, the "garden of his own house" (2 Kings 21:17, 18; 2 Chr. 33:20), but not in the City of David among his ancestors.