Forty Years with Credit for Time ServedBy Rabbi Jack Abramowitz
G-d told Moshe and Aharon that He would kill off everyone then over the age of 20 in the wilderness. This would take place over the next 40 years, one year for each day the spies were gone. (Actually, they died over the course of 38 years; they were in the desert two years already and they wandered for a total of 40 altogether.) G-d excluded Caleb and Joshua from the decree. (You’ll notice that not even Moshe himself is excepted. Of course Moshe didn’t heed the evil report of the ten spies! He died in the wilderness because of his own error as we shall see, but G-d with His foreknowledge no doubt knew this was coming.)
When Moshe communicated G-d’s decree to the nation, they were understandably upset. Some overcompensated by trying to take the land right then. “Don’t bother,” Moshe told them. “You won’t succeed because G-d’s not with you.” They tried anyway and were easily beaten down by Amalekite and Canaanite forces.
Changing subjects, G-d told Moshe that after the Jews entered Israel, all animal sacrifices were to be accompanied by flour offerings. There were specific quantities of wheat flour mixed with oil and of wine for each type of animal used as a sacrifice.