After Manasseh’s son, Amon, was assassinated (2 years after taking the thrown), Josiah was made king. He was only 8 at the time of his inauguration.
Note
Amon was made king at 22 and died at 24. Josiah was 8 at that time, so Amon was 16 when Josiah was born. Manasseh would have lived alongside Josiah until he was ~6 years old.
Josiah was not like his father. At the age of 18, he turned to God. At 20, he began tearing down the shrines of his father and grandfather. At 26, he worked to purify the temple and the land. He revived the priesthood’s legacy and they found the book of the law and read it aloud before him. He tore his robe, knowing his sins.
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