Why does it say "Yesh Davar?"
Rav Sadya Gaon: Sometimes it seems that there is something new - but it already was before us.
Rashi: If it seems that there is something new, this is because "Ein Zichron la'Rishonim" (11; it was forgotten), but it already was.
Ibn Ezra: Usually, "Yesh" refers to something sporadic, e.g. "v'Yesh Asher Yihyeh he'Anan" (Bamidbar 9:20), "Yesh Mefazer v'Nosaf" (Mishlei 11:24).
Rashbam: Is there even one matter that is new? No. If one will tell you that there is, it is not true - "Kevar Hayah."
Why does it say "Kevar Hayah l'Olamim"?
Ibn Ezra: Olamim is like Zemanim. The same applies to "Tzur Olamim" (Yeshayah 26:4), "Malchusecha Malchus Kol Olamim" (Tehilim 145:13), "Teshu'as Olamim" (Yeshayah 45:17) - salvation that is eternal, or 1 many times 2 .
R. Avigdor: "L'Olamim" is written without a Vov, to hint that everything was decreed in the six days [of creation].
Seforno: Something new in our days is already in the chronicles of earlier generations.
Metzudas David, Metzudas Tziyon: It already was, before we were born. L'Olamim is like b'Olamim. We find like this - "Bocher Atah l'Ven Yishai" (Shmuel I, 20:30) is like b'Ven Yishai.
So explains the Magihah (in Toras Chayim.
Metzudas Tziyon: This is like "v'Avado l'Olam" (Shemos 21:6).