What is the meaning of "Neranenah bi'Yshu'asecha"?
Rashi: When Hashem will save you, we will all sing to Him.
Radak: When Hashem will fulfill all your requests and return you safely from the war, we will sing about your salvation.
Malbim: We will sing about your salvation, for this was your heart's desire, that when we go out to greet the troops, we will sing about the salvation done for you before we arrive.
What is the meaning of "uv'Shem Elokeinu Nidgol"?
Yalkut Shimoni (Shir ha'Shirim 986): Hashem made Yisrael Degalim, so Bnei Reuven will be recognized by themselves, and Bnei Shimon by themselves 1 , like the angels.
Rashi: We will gather and do valiantly.
Radak: In His name we will raise our flag and banner.
Michtav me'Eliyahu (1, p.93): All the Shevatim need to join together to one purpose. The order is a safeguard lest they switch, and guards unity. (See Ramban Bamidbar 2:2 who gives reasons for the direction in which each Degel was. - PF)
Why does it say "Yemalei Hashem Kol Mish'alosecha"?
Radak: Refer to 20:5:1:2.
Malbim: Since Hashem fulfilled your heart's desire, all the more so He will fulfill what you request with your mouth!
