Verse 7 states that Caleb was 40 years old when he was sent out as a spy
from Kadesh-barnea. He brought a good report, but the people of Israel didn’t
listen to him and Joshua. Therefore, God caused Israel to wander a year for
each day they spend spying out the land. They wandered for 40 years.
Verse 10 states that Caleb didn’t die in the wilderness, as the others
did. He and Joshua were obedient, thererfore God kept them alive, as He
promised. The wilderness wandering lasted 40 years, and Caleb states that the
land of Canaan was conquered in 5 years, therefore he is 85 years old, and
ready to receive the promise of God in the land of Canaan.