12 Now when he was in affliction, he implored the Lord his God, and humbled himself greatly before the God of his fathers, 13 and prayed to Him; and He received his entreaty, heard his supplication, and brought him back to Jerusalem into his kingdom. Then Manasseh knew that the Lord was God. 14 After this he built a wall outside the City of David on the west side of Gihon, in the valley, as far as the entrance of the Fish Gate; and it enclosed Ophel, and he raised it to a very great height. Then he put military captains in all the fortified cities of Judah. 15 He took away the foreign gods and the idol from the house of the Lord, and all the altars that he had built in the mount of the house of the Lord and in Jerusalem; and he cast them out of the city. 16 He also repaired the altar of the Lord, sacrificed peace offerings and thank offerings on it, and commanded Judah to serve the Lord God of Israel. 17 Nevertheless the people still sacrificed on the high places, but only to the Lord their God. 18 Now the rest of the acts of Manasseh, his prayer to his God, and the words of the seers who spoke to him in the name of the Lord God of Israel, indeed they are written in the book of the kings of Israel. 19 Also his prayer and how God received his entreaty, and all his sin and trespass, and the sites where he built high places and set up wooden images and carved images, before he was humbled, indeed they are written among the sayings of Hozai. 20 So Manasseh rested with his fathers, and they buried him in his own house. Then his son Amon reigned 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.