Deuteronomy 1:34-36

And the LORD heard the voice of your words, and was wroth, and sware, saying,

The Lord ... was wroth. In consequence of this aggravated offence-unbelief followed by open rebellion-the Israelites were doomed, in the righteous judgment of God, to a life of wandering in that dreary wilderness, until the whole adult generation had disappeared by death. The only exceptions mentioned are Caleb, and Joshua, who was to be Moses' successor.