All commentators will tell you that this section of Mark’s Gospel is an added second ending. In verse 15 our Missal omits the words: Jesus reproaches them “for their incredulity and obstinacy because they refused to believe.” This fact is illustrated in the passage from Acts and is a constant theme in Mark. Hopefully it is a lesson for us.
Ascension marks the beginning of the first Christian Novena. The apostles were told to go to Jerusalem and WAIT to receive Power. They did not know it would be only ten days. They were of one heart and mind in prayer.
Despite their disbelief, the apostles were commissioned to go out to the world and proclaim the Gospel. “Going out they preached everywhere, the Lord working with them and confirming the word by the signs that accompanied it”.
Traditionally we begin today the Novena for Christian Unity. We wait on the Holy Spirit. “It is” he said ”what you have heard me speak about: John baptised with water but you, not many days from now, will be baptised with the Holy Spirit”.