One of the most fascinating aspects of today's celebration of Jesus’ ascension is that the gospel we employ for our liturgical reading mentions nothing about Jesus' ascension. Though most of us presume the next thing Jesus does after he assures his disciples, "I am with you always, until the end of the age," is to start rising into heaven, Matthew never says that. His gospel ends at this point.
Scripture scholars have been warning us for a long time that we can't take for granted one evangelist knows what any other evangelist wrote. Experts debate whether John was familiar with Mark, Matthew and Luke. But everyone agrees Matthew and Luke knew only Mark (the first evangelist) and they're also convinced Matthew and Luke didn't know one another. So we can't argue that Matthew didn't need to finish his narrative with an actual ascension because "everybody" already knew that's what happened. Unless someone reads Luke/Acts, he or she doesn't know that. (There's no ascension in Mark's canonical gospel.) Besides, the meeting Matthew describes between Jesus and his disciples takes place on a mountain "in Galilee." The ascension event Luke depicts in our first reading takes place outside Jerusalem on the Mt. of Olives, at least 60 miles south of Galilee!
Knowing this, Luke's opening Acts narrative of Jesus ascending into heaven after 40 days of instructing "the apostles he had chosen" is, to say the least, problematic.
One key to unlock the confusion is to understand that it took Jesus' earliest followers a long time to "sort things out." They certainly didn't have everything together by Pentecost evening. Most people don't realize there's at least a 40 year interval between Jesus' death and resurrection and the writing of the first gospel.
Paul's letters are the only writing which have come down to us from that interval. That's why our Ephesians passage is so significant. Though Paul originally expected Jesus to triumphantly return during his lifetime, he doesn't seem to have been too worried about Jesus' zip code before that return. The Apostle certainly believes the risen Jesus is present in the midst of his followers. (He even told the Corinthians, "Jesus appeared to me!") But at the same time he can theologize, "(God) worked in Christ, raising him from the dead and seating him at his right hand in the heavens ... And he put all things beneath his feet and gave him as head over all things to the church, which is his body . . . .”
Paul's being more poetic than geographic. He's concerned his readers understand that the risen Jesus is at the center of their life and faith. He employs symbolic language to convey that reality.
In a parallel way, Matthew wants to convince his community that Jesus both commissions them to carry on his ministry" to all nations," and guarantees; "I am with you always, until the end of the age."
Luke, the first author of the Christian Scriptures to believe Jesus isn't going to return in the Parousia during his lifetime, has a somewhat different agenda. He's concerned with those in his community who are still "looking at the sky," spending their time planning for Jesus' return instead of carrying on Jesus' ministry. The "two men dressed in white garments" are telling Jesus' followers, "Ok, you've got work to do; so do it!"
Perhaps the theological diversity in today's three readings should inspire us to respect the theological diversity that exists in Christianity even today.
Our sacred authors constantly tell us that one theology doesn't fit everyone's faith needs.