Hebrews 3:17-19

17And with whom was He angry for forty years? Was it not with those who sinned, whose dead bodies were scattered in the desert?

18And to whom did He swear [an oath] that they would not enter His rest, but to those who disobeyed [those who would not listen to His word]?

19So we see that they were not able to enter [into His rest—the promised land] because of unbelief and an unwillingness to trust in God.