John Gill Commentary Numbers 14:31

"But your little ones, that ye said should be a prey, them will I bring in, and they shall know the land which ye have rejected." — Numbers 14:31 (ASV)

But your little ones, which you said should be a prey To the Canaanites (Numbers 14:3); them will I bring in into the land of Canaan, and so fulfill the promise made to Abraham, Isaac, and Jacob; for the unbelief of this congregation did not make the faith, or faithfulness of God, of none effect.

and they shall know the land which you have despised; they shall know what a good land it is by experience, and shall possess and enjoy it with approbation, delight, and pleasure, which they, believing the spies, rejected with loathing and disdain.