The spies that Moses chose were all great men, explains Rashi, and yet Rashi seems to contradict this when he says that Moses prayed that his student Joshua would not follow them. In Rashi’s retelling, Moses prayed that God would save Joshua from the advice of the spies. Sometimes the person is good, but their advice is no good. The spies were instructed to take a tour of the land and report on what they see. Moses sensed that they planned to go one step further, they were also going to give advice. And so Moses prayed, explained the Lubavitcher Rebbe, that Joshua would not give advice together with them.