I shall share some thoughts about the Ascension as it relates to the Eucharist which also may speak to your faith, as it does to mine.
When Jesus ascends into heaven, he enters heaven as our Great High Priest. In the Jewish worship offered in the Temple, the High Priest would enter annually into the inner sanctum, the Holy of Holies, on the Day of Atonement to offer blood sacrifice for the sins of the People. The author of the Letter to the Hebrews compares Jesus’ entry into heaven to this entry of the High Priest into the Holy of Holies. The Ascended Christ brings his own Sacrifice on the Cross for our sins before God and opens the way for us to follow him to heaven. (See Hebrews 4:14; 9:11; 10:19,20)
In heaven Christ is our Priest. He presides over the Heavenly Liturgy which includes the angels and saints and all the blessed of heaven. As Priest he offers his One Sacrifice, once offered on the Cross, i.e. himself in his Body and Blood. The Catechism (#1187) says about this Heavenly Liturgy:
"The liturgy is the work of the whole Christ, head and body. Our high priest celebrates it unceasingly in the heavenly liturgy, with the holy Mother of God, the apostles, all the saints, and the multitude of those who have already entered the kingdom."
Christ also makes intercession for us in heaven. (See Hebrews 7:25) This is why at our Sunday Mass, at the time of the Intercessions, we say we are joining our Intercessions with those of Christ.
When we celebrate our Eucharist on earth, we spiritually ascend to heaven, to participate by faith in the Heavenly Liturgy with Christ. I have learned a great deal about this "ascension in the liturgy" from an Orthodox Priest and Liturgical scholar, Fr. Alexander Schmemann. He writes:
"But the liturgy of the Church is always...a lifting up, an ascension. The Church fulfills itself in heaven in that new eon which Christ has inaugurated in His death, resurrection and ascension, and which was given to the Church on the day of Pentecost as its life..." (For the Life of the World, p.42)
The U.S. Bishops say much the same thing about Christ’s Presence in the Eucharist:
"Christ does not have to leave where he is in heaven to be with us. Rather, we partake of the heavenly liturgy where Christ eternally intercedes for us and presents his sacrifice to the Father and where the angels and saints constantly glorify God and give thanks for all his gifts." ( "The Real Presence of Jesus Christ in the Sacrament of the Eucharist: Basic Questions and Answers," USCCB, June 2001)
In the oldest Roman Eucharistic Prayer (Now called Eucharistic Prayer I), after the Consecration, the Priest prays:
"In humble prayer we ask you, almighty God:
command that these gifts be borne
by the hands of your holy Angel
by the hands of your holy Angel
to your altar on high
in the sight of your divine majesty,
so that all of us, who though this participation
at the altar
receive the most holy Body and Blood of your Son,
may be filled with every grace and heavenly blessing."
This prayer refers to the altar in heaven mentioned in several places in the Book of Revelation (). Christ is Present at that altar. As one commentator says: "The community in the church on earth is mystically gathered at God’s altar on high." (Paul Turner, The Supper of the Lamb, p.89) Our altar on earth participates in the Heavenly Altar.
The question as to how Christ is now in heaven (after his Ascension), yet Really Present in the earthly Eucharist, "under" the appearance of the Consecrated Bread and Wine, was the subject of some debate in the Middle Ages. Does he "come down" from heaven to be Present in the earthly Eucharist? The Bishops answer he does not; and yet he is truly Present to us at the Eucharist.
For myself, I understand this matter in this way: first, when we speak of Christ’s being in heaven, we cannot really say "he is up in heaven" or that "he comes down from heaven" (i.e. after his Ascension). Heaven is not a location like a geographical location on earth. The Catechism (#2794) says: "[Heaven] does not mean a place (‘space’), but a way of being; it does not mean that God is distant, but majestic. Our Father is not ‘elsewhere’: he transcends everything we can conceive of his holiness."
I am able to understand this by imaging heaven as a "dimension," so to speak, that transcends our world of time and space. Perhaps I first thought this from a passage (again) from Fr. Alexander Schmemann. He speaks of the Liturgy of the Eucharist as a "journey into the dimension of the Kingdom [of God]":
"We use this word ‘dimension’ because it seems the best way to indicate the manner of our sacramental entrance into the risen life of Christ. Color transparencies ‘come alive’ when viewed in three dimensions instead of two. The presence of the added dimension allows us to see much better the actual reality of what has been photographed. In very much the same way, though of course any analogy is condemned to fail, our entrance into the presence of Christ is an entrance into a fourth dimension which allows us to see the ultimate reality of life." (For the Life of the World, p.26-27)
(Because of Einstein, we often call time the fourth dimension, but Schmemann is not referring to that description; indeed, his fourth dimension would be eternity)
As a "fourth dimension," paradoxically heaven is nowhere and everywhere. It is like the Ultimate Reality "behind" our earthly reality. (We have to keep using spatial language for a reality that is not spatial) I can image the Eucharist, then, as opening, a portal, so to speak, to heaven: "the gates of heaven."
The Psalmist says: "I rejoiced with those who said to me, ‘Let's go to the Lord's house!’ Now our feet are standing in your gates, O Jerusalem." (Psalm 122:1-2)
The Psalmist was speaking of the earthly Jerusalem. With the Eucharist, I am thinking of the heavenly Jerusalem, about which I have written quite a bit lately. What I am saying is that in the Eucharist we are standing spiritually within the heavenly gates of the New Jerusalem.
When I think this way, I think of C.S. Lewis’s The Lion, the Witch, and the Wardrobe, where four children discover in a closet wardrobe a doorway to a magical country called Narnia. (Narnia also is not on the same time as our world).
Another way of seeing this is that heaven and earth join in the Eucharistic celebration. Christ does not leave heaven, nor do we literally leave earth, but we meet and receive the Risen Christ in heaven in the Eucharist, the "meeting place" at "the gates." Again the Psalmist says: "Open for me the gates of righteousness; I will enter and give thanks to the Lord. This is the gate of the Lord through which the righteous may enter. I will give you thanks, for you answered me; you have become my salvation." (Psalm 118.19-21)
Listen HERE to Handel's "Lift up your heads, O ye gates" sung by the Brandemburg Consort and the Choir of King's College Cambridge