Commentators overwhelmingly identify 'the king' not as an Israelite king like David, but as Artaxerxes, the king of Persia. Scholars like Barnes, Ellicott, and Gill note that he went beyond just exempting temple workers from taxes; he established a daily salary for the singers from the royal treasury. This highlights God's remarkable providence, using a foreign ruler to ensure the proper functioning and vibrancy of worship in Jerusalem.