Everyone was to obey Haggai (Hag 1:12-1:12)

“Then Zerubbabel,

The son of Shealtiel,

With Joshua,

The son of Jehozadak,

The high priest,

With all the remnant

Of the people,

Obeyed the voice

Of Yahweh

Their God.

They obeyed

The words

Of the prophet Haggai.

Yahweh,

Their God,

Had sent him.

The people feared

Yahweh.’”

The rulers and the remaining people of Jerusalem gathered to hear the voice of Yahweh, via the prophet Haggai.  This included the governor of Judah, Zerubbabel, and the high priest Joshua, as mentioned earlier.  They would obey Haggai as the voice of Yahweh, since they feared Yahweh.  Yahweh had sent them Haggai as a prophet to speak in his name.