Rashi: He will permanently cover and hide it from Yisrael.

Radak: He will destroy and nullify death, i.e. due to occurrences, e.g. murder, like in Galus. Natural death will not cease.

Malbim: Death, of Anshei Gog who camped against Har Tziyon, will swallow the false Emunos (refer to 25:7:1:2, 25:7:3:3). It will be permanent, for they will see Gog's fall and the plague against the afflicters of Yerushalayim. They will return to belief in Hashem, and recognize the true creed.

Pesachim 68a: Death will cease from Yisrael. Nochrim will live long lives [but not forever]. They will be in the world to come to serve us - "v'Amdu Zarim v'Ra'u Tzonchem..." (61:5).

Radak: All of Yisrael cried constantly in Galus from the evil that they did to us. Hashem will wipe the tears away; there will be no more afflictions.

Radak: They were scattered in the entire land, and had shame everywhere.

Malbim: Now, the entire land reviles them, and says 'why do you hope for salvation? You lost your hope - "Ein Yeshu'asah Lo vEi'lokim Selah" (Tehilim 3:3)!

Radak: It will truly be so, for Hashem spoke. What He says is fulfilled in any case.