There was only a little time. Soon Jesus would be tried and crucified: His earthly ministry would soon be over and the trainee apostles had to be ready to take over as messengers of the gospel.

Military missions intend to impose their will on the people. Not so with Jesus. At no point in His ministry did the Lord ever make people follow Him or serve Him.

As the disciples went out on mission, without Jesus for the first time, He explained the dangers which they would face in the future (after He had gone back into heaven).

Jesus had been warning His disciples about the persecution which would come to Him and to them. It would not be random acts of hatefulness but part of a coordinated assault on the Kingdom of God.