What does Zechariah 11:4 mean?

Open your doors, Lebanon, that the fire may devour your cedars.

Wail, cypress tree, for the cedar has fallen, because the stately ones are destroyed. Wail, you oaks of Bashan, for the strong forest has come down.

A voice of the wailing of the shepherds! For their glory is destroyed: a voice of the roaring of young lions! For the pride of the Jordan is ruined.

Their buyers slaughter them, and go unpunished. Those who sell them say, ‘Blessed be Yahweh, for I am rich;’ and their own shepherds don’t pity them.

For I will no more pity the inhabitants of the land,” says Yahweh; “but, behold, I will deliver the men everyone into his neighbor’s hand, and into the hand of his king. They will strike the land, and out of their hand I will not deliver them.”

So I fed the flock of slaughter, especially the oppressed of the flock. I took for myself two staffs. The one I called “Favor”, and the other I called “Union”, and I fed the flock.