John Gill Commentary Numbers 14:23

"surely they shall not see the land which I sware unto their fathers, neither shall any of them that despised me see it:" — Numbers 14:23 (ASV)

Surely they shall not see the land which I swore to their
fathers
Not possess and enjoy the land of Canaan, which the Lord by an oath had promised their fathers, Abraham, Isaac, and Jacob, to give it to their seed; and now he swears that these men, who had so often tempted him, and been disobedient to him, should not inherit it; so the Targums of Jonathan and Jerusalem take it for an oath; see (Hebrews 3:11Hebrews 3:18) ;

neither shall any of them that provoked me see it ;
that provoked him by the ill report they had brought of the land, by their unbelief, by their murmurings, and mutiny.