Deuteronomy 2:14-15

And the days in which we came from Kadesh-barnea, until we were come over the brook Zered, were thirty and eight years; until all the generation of the men of war were consumed from the midst of the camp, as Jehovah sware unto them. Moreover the hand of Jehovah was against them, to destroy them from the midst of the camp, until they were consumed.