For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counselor, The mighty God, The everlasting Father, The Prince of Peace.
All Commentaries on Isaiah 9:6 Go To Isaiah 9
Ambrose of Milan
AD 397
Accordingly, to call the nations to the grace of his resurrection—which is the rich and fertile land that bears everlasting fruits, fruits a hundredfold and sixtyfold—he bowed his shoulder to labor, bowed himself to the cross, to carry our sins. For that reason the prophet says, “whose government is on his shoulder.” This means, above the passion of his body is the power of his divinity, or it refers to the cross that towers above his body. Therefore he bowed his shoulder, applying himself to the plow—patient in the endurance of all insults, and so subject to affliction that he was wounded on account of our iniquities and weakened on account of our sins.