2 Kings 12 - As Joash (Jehoash) began his reign, remember he was a young boy as he started. Eventually he would recognize things that should be done and he told the priests to collect money to pay for repairs to the Temple. One thing of note is that in verses 6 and 7 Joash got older and found that the work on the Temple had not been done. Money was collected but nobody did the work. That is significant, remember this. I believe this will answer why something happened later in Jehoash's kingship. When the priests got down to business and paid the workers, it says in verse 15 that the men who did the job were so faithful in their work that they weren't required to give account of their use of the money. It was so evident that they were doing an excellent job. As you end this chapter you read of the murder of Joash. Why? Think about this as you will eventually read 2 Chronicles 24.
2 Kings 13 - Jehoahaz becomes king of Israel, the northern kingdom. He immediately continues in the sins of Jeroboam, but he repents, verse 4, and God brought a deliverer to help him. His son, Joash (not the same as the king of Judah), became king of Israel. He met with Elisha and one of the last things Elisha did was to encourage Joash to trust God for victory over Syria. Joash apparently was not fully trusting God and simply "went through the motions" of having faith. As a result, he had only a partial and temporary victory over the Syrians. Elisha would die, but even in his death a miracle was performed. When a man's corpse was placed in Elisha's tomb and touched Elisha's bones, the man immediately came back to life! What a surprise that must have been for the men who had just place him in that tomb!
2 Chronicles 24 - This is the Chronicles account of Joash's rule as king of Judah. He was greatly influenced by Jehoiada, the priest. But after Jehoiada died Joash reverted to sinful practices like so many before him. However, I personally believe that when his order to the priests to have the Temple fixed and when the priests delayed carrying out that order, that Joash had a turning point. He wasn't respected and this made him resentful. He would eventually show that after Jehoiada died. Joash would even have Jehoiada's son, Zechariah, killed. Eventually Joash would die but in disgrace, verse 25.