Jesus said, “The time will come when you will want very much to see one of the days of the Son of Man. But you will not see it.” Luke 18:22.
When the disciples were with Jesus they never fully comprehended him or his mission. They did not fully recognize that Jesus was divinity clothed in humanity. They had allowed the prevailing doubt to cloud their minds and judgment. In fact, Thomas had to put his finger into the wound on Jesus' side to believe. Peter had denied Jesus during his humiliation.
The disciples did not truly comprehend what they had been apart of until they were filled with the Holy Spirit after Jesus ascended to heaven. They then studied prophesy and their eyes were opened and for the first time they understood the plan of salvation. Now they longed to be with him in person again.
Similarly, today we cannot understand spiritual things without the enlightenment of the Holy Spirit. Once we are filled with the Holy Spirit, we will be able to be Jesus and share Jesus with others. This will result in changed lives and a better world.
Jesus saw the corrupt and oppressive government of his time. Yet, he never interfered with government operations or criticized their behavior. Instead, he determined to make a change by reaching out to the individual. Once a change is made at this level, it will have a much greater impact.