King Yoshiyahu's Reforms and the Discovery of the Torah Scroll

In 2 Melachim 22:2 it says "And he did what was right in the eyes of the Lord, and he walked in all the ways of David his father, and he turned away neither right nor left." Why is it that it mentions this, but then goes on to talk about finding the law, he tears his robes (in repentance?) then goes on to destroy the objects of idol worship in the temple. As if he, at age 28 has allowed this sinfulness in the temple for so long, but no longer. Is being seen right in the eyes of the Lord different than we imagine? Did he or did he not participate in the temple worship? By his tearing of his robes, it suggests that he did not know. By him destroying these objects at age 28, suggests he did not know. Maybe the Lord is looking at his heart, more than His actions? Or it is an introduction to his "story" of him following God's ways in the future? Sorry for the complicated question

Thank you for your inquiry.
King Yoshiyahu ascended to the throne at the tender age of eight, succeeding a lineage of monarchs who had not only neglected the temple but had desecrated it with idol worship. At the age of 18, Yoshiyahu initiated significant repairs to the temple. It was during these renovations that a sacred scroll was discovered in the Holy of Holies. Intriguingly, the scroll was opened to a passage not at the beginning of Genesis but near the end of Deuteronomy 28:36, which reads: יולך ה' אתך ואת מלכך אשר תקים עליך אל גוי אשר לא ידעת.
Realizing the gravity of the warning, Yoshiyahu tore his garments, a gesture reflecting his recognition of God's immense displeasure. He responded decisively, purging the temple of all idols and restoring its sanctity and purity. Yoshiyahu merited to die peacefully yet despite his profound repentance and efforts to amend the past, Yoshiyahu was destined to die peacefully since he was a tsadik before the full consequences of prior transgressions — which included punishment and exile — were realized.
Thus, while Yoshiyahu was indeed a righteous king, a tzaddik, there was still retribution for the sins of the past.
Wishing you well.

Book of Kings,2 chapters 22-23