Why does it say "l'Olam"?!
Radak: You said that Shamayim should exist, and it came in to existence. That word and desire will be established forever; Shamayim and its legions will not cease.
Malbim: Refer to 118:89:2:3.
Is Hashem's word established only in Shamayim, but not on the land?!
Bereishis Rabah (53:4): Hashem's word to Avraham in Shamayim "la'Mo'ed Ashuv Elecha ka'Es Chayah" (Bereishis 18:14) is established.
Shemos Rabah (38:1): We read this like ka'Shamayim; Your word is [Emes, and] established like Shamayim.
Malbim: The upper world and lower world that You created, both persist via Your word, but there is a difference. The upper world, the same individuals (e.g. angels) persist; in the lower world, [individuals die, but] the species persists. Regarding Shamayim, Your word is established forever without change.
