“He was sixteen years old when he began to reign … and he did what was right in the eyes of the Lord” (v3). Most of kings of Israel and Judah did not lead the people righteously. Young King Azariah was one who chose to follow God (the “high places” not taken away seems to refer to allowing people to worship God outside Jerusalem, but not idolatry v4). Azariah’s faithfulness was tested because he had leprosy and couldn’t govern the people directly (v5).
“The Lord touched the king” (v5). The tragedy of leprosy did not drive Azariah away from God. Instead, in a time of evil, he had the courage to choose God’s way.