In a scene at the very end of Matthew’s Gospel, Jesus gives us a “great commission” which in part answers the question raised by the disciple in the stain glass window who upon seeing Jesus ascend into heaven asks his friend , “What do we do now?
The Great Commission Matthew 28 (16-20)
Then the eleven disciples went to Galilee, to the mountain where Jesus had told them to go. When they saw him, they worshiped him; but some doubted. Then Jesus came to them and said, “All authority in heaven and on earth has been given to me. Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age.”
For Catholic’s the main way we know that Jesus is with us until the end of the age is through the celebration of the mass.
Here is a video with a number of powerful quotes about what the mass means to those who believe in it.
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