C. F. Keil and Franz Delitzsch on 2 Chronicles 24:21-22

2Ch 24:21-22

And they (the princes and the people) conspired against him, and stoned him, at the command of the king, in the court of the temple. This זכריה is the Ζαχαρίας whose slaughter is mentioned by Christ in Mat 23:36 and Luk 11:51 as the last prophet-murder narrated in the Old Testament, whose blood would come upon the people, although Matthew calls him υἱὸς Βαραχίου. According to these passages, he was slain between the temple and the altar of burnt-offering, consequently in the most sacred part of the court of the priests. That the king, Joash, could give the command for this murder, shows how his compliance with the princes’ demands (2Ch 24:17) had made him the slave of sin. Probably the idolatrous princes accused the witness for God of being a seditious person and a rebel against the majesty of the crown, and thereby extorted from the weak king the command for his death. For it is not said that Joash himself worshipped the idols; and even in 2Ch 24:22 it is only the base ingratitude of which Joash had been guilty, in the slaughter of the son of his benefactor, which is adduced against him. But Zechariah at his death said, “May the Lord look upon it, and take vengeance” (דּרשׁ, to seek or require a crime, i.e., punish it). This word became a prophecy, which soon began to be fulfilled, 2Ch 24:23.