Why does it say "v'Agid Lecha me'Az b'Terem Tavo [Hishmaticha...]"?
Rashi: Refer to 48:4:1:1.
Radak: The decree that will come, I told you before it came. Had I not done so, perhaps you would say 'my idol did these decrees that come; my image commanded that they come.'
Malbim: [Because you are hard,] I needed to inform you beforehand, lest you say "my idol did them." I needed to publicize it via a Navi shortly before it came, lest you say "my image commanded them." I.e. even though I already told the Navi, and you cannot say that the idol did them, you could say that the idle or image commanded about the matter that Hashem did; they are His Sheluchim 1 .
Malbim: There were two kinds of idolaters. Some believed that the idol is divine - they would say that it did the miracle. Others believed that it is merely an intermediary between Hashem and man - they would say that it was the intermediary between Hashem and the world, and commanded that it be carried out.