The 50th Day of Easter:
Pentecost Sunday

Pentecost – Harvest of the Holy Spirit
(Edited excerpt adapted from Fr. James Puthuparampil OIC, Bethany Ashram:)

The liturgy of Pentecost is one of the privileged occasions for us
to bear witness to the axiom that the norm of prayer is the norm
of faith ... lex orandi lex credendi.

Since this understanding is deeply biblical in character, before dealing with the liturgical aspect, it would be good to highlight here Christ’s words about the person and activities of the Holy Spirit:
If I do not go away, the Counselor will not come to you;
but if I go, I will send Him to you.Jn 16:7
Read more, click here to full Pentecost post.

Excerpt from Bishop Ware, "The Orthodox Way":
Note the theological epiphanies through the Spirit:
1
Incarnation;
Baptismal Theophany;
Trans-
figuration;
Pentecost;
2
The Sciptural Word in the Church, cf Acts 2.42 re "the breaking of the bread and the prayers": Anaphora, Anamnesis, Epiclesis;
3
Communio in the Name as "communio sanctorum" and "communio in sacris": Theosis as Christification of "our whole life in Christ" -- the Presence and Parousia of Emmanuel, God is with us!

And thus:
The Coming of the Holy Spirit: Pouring oil to overflowing
EXCERPT:
"It has been said that the Orthodox Church is the Church of the Holy Spirit
... Every prayer, every liturgical and sacramental action of the Eastern Church is done through an invocation to the Holy Spirit. His Presence and Activity ... is truly the original Pentecostal Church.

"Our mystical life is one of constant 'in-spiration' and our prayer life is our living link with the Spirit; ... which is, as the Fathers taught, the 'epiclesis of our Lord and Saviour' which we constantly call down on our souls to conform them to Christ.

"In the Spirit, we become
a community of priests, the Royal Priesthood,
called upon to constantly invoke the sacramental and mystical Name of Jesus
over ourselves and those around us
and upon the entire world God has created.
We do this as a priestly exercise to sanctify everything
in Christ
through the Holy Spirit
to the Glory of God the Father."
(end excerpt



All icons, and particularly this Icon of Hospitality and the Holy Trinity, are a liturgical mystagogy of the Parousia and Judgement at the Eschaton.
Written by the hand of St. Andrei Rublev some 25 years after he received the commission, the entire Icon mediates a sacramental epektasis of the Kingdom of God and the Heavenly Liturgy:
the Eucharist at the Heart of the Trinity --
the Eucharistic Life that is given us in the Original and Ongoing Pentecost of the Church of Christ that is One, Holy, Catholic, and Apostolic.