'Forty Years' in the Bible

Indeed, for forty years the Israelites traveled through the desert until all the men old enough to fight when they left Egypt, the ones who had disobeyed the Lord, died off. For the Lord had sworn a solemn oath to them that he would not let them see the land he had sworn on oath to give them, a land rich in milk and honey.

I was forty years old when Moses, the Lord's servant, sent me from Kadesh Barnea to spy on the land and I brought back to him an honest report.