What are "[Cherpah] u'Gedufah Musar u'Meshamah"?
Rashi: They are, respectively, disgrace, afflictions and astonishment.
Radak: The grammatical form of Gedufah is like Meluchah. It is [shame,] like "Cherpah"; the matter is repeated in different words to strengthen it. Musar is chastisement for the nations, like "v'Nivaseru Kol ha'Nashim" (23:48). Meshamah is astonishment at the great evil that will come upon you, like "Yishom v'Yishrok" (Yirmeyah 19:8).
Malbim: Your Cherpah and Gedufah 1 is that they will revile you. This will be Musar and Meshamah for the nations around you. They will be punished for reviling Kedushas Yisrael.
Malbim: Megadef is Mecharef (reviling) something with Kedushah. The Cherpah will be Musar, and the Giduf will be Meshamah for the nations. Via reviling you for your evil deeds, it is proper that they take Musar how Hashem punished you for evil deeds. For Giduf of Torah and Elokei Yisrael there would be desolation; they will be punished. They should have taken Musar and known that when I punished you "b'Af uv'Chemah uv'Sochechos Chemah", it is of Hashgachah. They should not have reviled Torah and Elokei Yisrael!
The verse begins in third person ("v'Haysah"), and ends in second person ("Sevivosayich ba'Asosi Vach")!
Radak: Verses often switch like this.
What are "b'Af uv'Chemah uv'Sochechos Chemah"?
Radak: This is repetition to strengthen the matter.
Malbim: It is evil judgments via revealed Af and hidden Chemah and revealed rebukes - all will know that I poured My anger on them.