2 Chronicles 23:13
And she looked, and, behold, the king stood at his pillar at the entering in, and the princes and the trumpets by the king: and all the people of the land rejoiced, and sounded with trumpets, also the singers with instruments of musick, and such as taught to sing praise. Then Athaliah rent her clothes, and said, Treason, Treason.
The moment is a public coronation, with Joash taking his place beside the pillar as he is acclaimed king. Around him stand the princes and the trumpeters, while the whole assembly rejoices and trumpets sound, and singers with musical instruments lead the praise. Athaliah witnesses the ceremony, then tears her garments and shouts treason, treason. Her cry is provoked by the discovery that the people have restored an heir of David to the throne she had taken for herself.