There are four Masses of Christmas, Vigil, Midnight, Dawn and Day, each with their own scripture readings – take your pick at this link. The Lectio attached uses the Gospel of the Day Mass.
Most people think of the Ascension of Jesus as being a ‘departure’ moment. Jesus was here and now he is gone. We imagine Jesus going up into the clouds and the disciples waving farewell from below.
This is an unhelpful image.
It is essential that we understand what does happen and what does not happen in the Ascension event.
It would be easy to wrongly think that in his ministry showed us how to build the city of God on earth, and now he has gone and the mission is left to us.