How did Manasses change after being taken to Babylon?

Manasses was twelve years old at his accession and reigned for fifty-five years in Jerusalem. He committed grave offenses before the Lord, embracing the abominations of the pagan populations whom God had driven out before the children of Israel. He rebuilt the elevated shrines his father Ezechias had demolished, erected altars to Baalim, planted sacred groves, and bowed down in adoration before the entire host of heaven—clarified by the Challoner annotations as the sun, moon, and stars.

Manasses introduced pagan altars into the very temple of the Lord, defying God's ancient declaration that His name would abide perpetually in Jerusalem. He established altars dedicated to the host of heaven across both courtyards of the sacred precinct. In the valley of Benennom, he made his own sons pass through the fire, gave himself over to magic arts, observed dreams, practiced divinations, and surrounded himself with sorcerers and enchanters, provoking divine wrath through repeated transgressions. He even set up a carved and molten statue within the house of God, directly violating the covenant delivered to David and Solomon that the Lord had chosen this temple and Jerusalem out of all Israel's tribes to place His name forever, promising that the children of Israel would never be driven from their ancestral soil provided they carefully observed the laws, ceremonies, and judgments mediated through Moses. Nevertheless, Manasses seduced the people of Juda and Jerusalem into evils far greater than those committed by the heathen nations destroyed before Israel.

The Lord addressed warnings to Manasses and his subjects, but they refused to heed the divine admonitions. Consequently, God summoned against them the commanders of the Assyrian army, who seized Manasses, bound him with chains and fetters, and carried him away to Babylon. While enduring intense distress in exile, Manasses prayed earnestly to the Lord his God and performed profound penance before the God of his ancestors. He entreated Him with persistent supplication, and the Lord heard his petition, returning him to his royal throne in Jerusalem. Through this deliverance, Manasses came to recognize that the Lord alone is God.

Upon his return, Manasses fortified the city of David by constructing a high exterior wall west of Gihon in the valley, extending from the entrance of the Fish Gate around the hill of Ophel, and stationed military commanders across all the fortified cities of Juda. He then purged the capital of idolatry, taking away foreign deities, removing the statue from the house of the Lord, and casting out of the city all the pagan altars built upon the temple mount and throughout Jerusalem. He repaired the altar of the Lord, presenting sacrifices of peace offerings and thanksgiving upon it, and commanded Juda to serve the Lord the God of Israel. Nevertheless, the people continued to sacrifice on the high places, though they offered them exclusively to the Lord their God.

The remaining acts of Manasses, his prayer to his God, and the prophetic words delivered by the seers who addressed him on behalf of the Lord God of Israel are preserved in the records of the kings of Israel. His prayer, the divine response granting his petition, all his offenses and contempt, and the specific sites where he erected high places, groves, and statues prior to his penance are recorded in the writings of Hozai. Manasses slept with his fathers, was buried within his own house, and his son Amon succeeded him as king.

Amon was twenty-two years old when he assumed the crown, and he ruled for two years in Jerusalem. He committed evil before the Lord just as his father Manasses had done, offering sacrifice to all the idols his father had fashioned and serving them. Unlike his father, however, Amon did not humble himself before the Lord as Manasses had humbled himself, but committed far greater sin. His servants conspired against him and slew him within his own house. However, the assembly of the people executed those who had slain King Amon, and they made his son Josias king in his stead.