Albert Barnes Commentary Numbers 14:9

"Only rebel not against Jehovah, neither fear ye the people of the land; for they are bread for us: their defence is removed from over them, and Jehovah is with us: fear them not." — Numbers 14:9 (ASV)

Their defense - literally, “their shadow,” that is, their shelter as from the scorching sun: an Oriental figure. Compare the marginal references.