Why did he tell those who fear to return home?
Malbim: Divine influence rests only on those prepared for it. This required preparation of Gevurah (to exclude one who fears), and preparation of Kedushah, to exclude those who kneeled; they were not worthy of a miracle.
What is the meaning of "v'Yitzpor"?
Rashi, based on Targum Yonasan: [They returned] in the morning. This is based on the Arame'ic Tzafra (morning).
Radak: It is to circle. Mitznefes (the [Kohen Gadol's turban] is called Tzefirah because it goes around his head. Veli'Tzfiras Tif'arah (Yeshayah 28:5) [is a crown].
Malbim: They will 'fly' (pursue the enemy quickly) like Tziporim (birds). They immediately went to Har ha'Gil'ad, and in the morning they went home. The victory would be that night; the fearful men would chase the fleeing Midyanites. The ones who kneeled went home immediately. They were idolaters, and not proper to join in the war at all, even to chase.
