A quality that is peculiar to the gospel of Mark is the lack of stories of the appearances of the risen Lord. The gospel this Sunday is actually considered to be added on at later time. Mark’s emphasis is to see the risen Christ reflected in discipleship which is part of the mission of the Church in the world.
The gospel of Mark was likely written to Christians who experienced the persecution of Nero and knew more was on the way. The invitation by Jesus here is to go to all the world, to the whole creation. To do this, the disciple needs a strong sense of mission or “being sent.”
In the Acts of the Apostles, it is important for Jesus to depart before the Holy Spirit is given in this profound way on the feast of Pentecost. The attention must be re-directed from the sky to the community of faith and beyond. This is also about Jesus surrendering the mission to the community. The time Jesus spent with the disciples as risen Lord was a continuation of preaching about the kingdom of God. The difference could have been the way the disciples heard the message.
The Ascension of Jesus is about the power of change and the possibility of transformation, about a God who was willing to reach out to humanity and bring us into divinity. St. Augustine put it this way…
Although Jesus ascended alone, we also ascend because we are in him by grace.