For as in the day of Midian You have shattered the yoke of their burden, the bar across their shoulders, and the rod of their oppressor.
The first words of this chapter plainly refer to the close of the foregoing chapter, where every thing looked black and melancholy: Behold, trouble, and darkness, and dimness - very bad, yet not so bad but that to the upright there shall arise light in the darkness (Psa 112:4) and at evening time it shall be light, Zac 14:7.
Commenting on Isaiah 9:1-7
For thou hast broken the yoke of his burden,.... Of Galilee, of the nation multiplied, of the spiritual inhabitants of it, whose joy was increased; and this is one reason of it, because they were delivered by the Lord from the burdensome yoke of the ceremonial law, which was broken off and abolished by Christ; and from the tyranny of Satan, the god of this...
The occasion of the "joy," the deliverance not only of Ahaz and Judah from the Assyrian tribute (Kg2 16:8), and of Israel's ten tribes from the oppressor (Kg2 15:19), but of the Jewish Christian Church from its last great enemy. hast--the past time for the future, in prophetic vision; it expresses the certainty of the event. yoke of his burden--the yoke with which he was burdened. staff of . .