New Defender's Study Bible Notes
24:20 Zechariah the son of Jehoiada. Joash forgot (or ignored) the fact that Jehoiada had saved his own life when he was a child (II Chronicles 22:10-12), and had been responsible for making him king in the first place, after which he was a faithful and effective counselor for Joash as long as he lived. When his son, Zechariah, attempted to provide the same godly counsel as that of his father, Joash exhibited criminal ingratitude by allowing him to be stoned (II Chronicles 24:21-22). It is probable that it was this Zechariah referred to by Christ as a martyred prophet (Luke 11:51).