Why does the writer give us this information? Is it simply to emphasize the depth to which the economy had sunk that even lowly bronze items needed careful protection? Is it rather to show the protection that the king needed when he left his house, a protection that was needed because of the hardship that people were blaming him for?
The foregoing may be true, but more important is another matter. Rehoboam, despite the idolatrous practices that he permitted in Judah, was yet routinely going to the temple to take part in the worship of God. He also did this with some show of ceremony. There was a procession of many guards carrying the shield.
There are two issues to consider here. First, it may be that worship in spirit and in truth no longer existed, and the king replaced it with ritualism. Second, it is a true sign of hypocrisy. This is the only proper description of the combined worship of false gods and the worship of the living and true God. As we have been told, Judah provoked the Lord to jealousy.
What may we say about the spiritual state of Judah at this time? The nation had not gradually declined from relative godliness to a gradually lower state. The spiritual decay was rapid and it would have been fatal if God, through his grace to his servant David, had not postponed its culmination in exile.
28 And as often as the king went into the house of the LORD, the guard carried them and brought them back to the guardroom.