'Thirty eight' in the Bible

The space in which we came from Kadesh Barnea until we were come over the river Zered was thirty eight years: until all the generation of the men of war were wasted out of the host, as the LORD sware unto them.

And the Levites were numbered from thirty years and above, and the tale of them in men, poll by poll, was thirty eight thousand.

And a certain man was there, which had been diseased thirty eight years.