12 And crying out to the Lord his God in his trouble, he made himself low before the God of his fathers, 13 And made prayer to him; and in answer to his prayer God let him come back to Jerusalem and to his kingdom. Then Manasseh was certain that the Lord was God. 14 After this he made an outer wall for the town of David, on the west side of Gihon in the valley, as far as the way into the town by the fish doorway; and he put a very high wall round the Ophel; and he put captains of the army in all the walled towns of Judah. 15 He took away the strange gods and the image out of the house of the Lord, and all the altars he had put up on the hill of the Lord's house and in Jerusalem, and put them out of the town. 16 And he put the altar of the Lord in order, offering peace-offerings and praise-offerings on it, and said that all Judah were to be servants of the Lord, the God of Israel. 17 However, the people still made offerings in the high places, but only to the Lord their God. 18 Now the rest of the acts of Manasseh, and his prayer to his God, and the words which the seers said to him in the name of the Lord, the God of Israel, are recorded among the acts of the kings of Israel. 19 And the prayer which he made to God, and how God gave him an answer, and all his sin and his wrongdoing, and the places where he made high places and put up pillars of wood and images, before he put away his pride, are recorded in the history of the seers. 20 So Manasseh went to rest with his fathers, and they put his body to rest in his house, and Amon his son became king in his place.

Matthew Henry's Commentary on 2 Chronicles 33:12-20

Commentary on 2 Chronicles 33:1-20

(Read 2 Chronicles 33:1-20)

We have seen Manasseh's wickedness; here we have his repentance, and a memorable instance it is of the riches of God's pardoning mercy, and the power of his renewing grace. Deprived of his liberty, separated from his evil counsellors and companions, without any prospect but of ending his days in a wretched prison, Manasseh thought upon what had passed; he began to cry for mercy and deliverance. He confessed his sins, condemned himself, was humbled before God, loathing himself as a monster of impiety and wickedness. Yet he hoped to be pardoned through the abundant mercy of the Lord. Then Manasseh knew that Jehovah was God, able to deliver. He knew him as a God of salvation; he learned to fear, trust in, love, and obey him. From this time he bore a new character, and walked in newness of life. Who can tell what tortures of conscience, what pangs of grief, what fears of wrath, what agonizing remorse he endured, when he looked back on his many years of apostacy and rebellion against God; on his having led thousands into sin and perdition; and on his blood-guiltiness in the persecution of a number of God's children? And who can complain that the way of heaven is blocked up, when he sees such a sinner enter? Say the worst against thyself, here is one as bad who finds the way to repentance. Deny not to thyself that which God hath not denied to thee; it is not thy sin, but thy impenitence, that bars heaven against thee.