Dear Parish Faithful,
When a sunbeam falls on a transparent substance, the substance itself becomes brilliant, and radiates light from itself. So too Spirit-bearing souls, illumined by Him, finally become spiritual themselves, and their grace is sent forth to others. (St. Basil the Great)
The Monday after Pentecost is the Day of the Holy Spirit (which makes today one of our parish "namedays"). The book entitled The Great Horologion offers the following description of this particular commemoration:
As it is the custom of the Church, on the day after every great Feast, to honour those through whom it came to pass - our Lady after the Lord's Nativity, Joachim and Anna after our Lady's Nativity, the holy Baptist the day after Theophany, and so forth - on this day we honour God the All-Holy Spirit, the Comforter promised by our Saviour to His disciples (JN. 14:16), Who descended upon them at holy Pentecost and guided them "into all truth" (ibid. 16:13), and through them, us.
Although not explicitly stated in the Nicene-Constantinopolitan Creed (you can understand why we shorten that to the Nicene Creed), the Holy Spirit is God, One of the divine and co-eternal Persons of the Holy Trinity. The Holy Spirit is
the Lord, the Giver of Life, who proceeds from the Father;
who with the Father and the Son together is worshiped and glorified;
who spoke by the prophets.
Only God gives life - rather than receives life - and only God is "worshiped and glorified." That is why the first three days of Pentecost - Sunday, Monday and Tuesday - are also called the Three Days of the Holy Trinity.
Looking back to the Feast of the Ascension which prepared the world for Pentecost, the Church Fathers - especially St. John Chrysostom - insightfully expressed this profound connection:
Now the angels have received that for which they have long waited, the archangels see that for which they have long thirsted. They have seen our nature shining on the King's throne, glistening with glory and eternal beauty.... Therefore they descend in order to see the unusual and marvelous visions: Man appearing in heaven.
And one saw miracles follow miracles, ten days prior to this our nature ascended to the King's throne, while today the Holy Spirit has descended on to our nature.
On high is His body, here below with us is His Spirit. And so we have His token on high, that is His body, which He received from us, and here below we have His Spirit with us. Heaven received the Holy Body, and the earth accepted the Holy Spirit. Christ came and sent the Spirit. He ascended and with Him our body ascended also.
What does it mean that the Holy Spirit was poured forth on all flesh? St. Basil, in his famous treatise On the Holy Spirit, offered the following "list" of the many and manifold gifts of the Holy Spirit:
Hence comes foreknowledge of the future, understanding of mysteries, apprehension of what is hidden, distribution of good gifts, the heavenly citizenship, a place in the chorus of angels, joy without end, abiding in God, the being made like to God, and highest of all, the being made God!
St. Basil also makes it clear that the struggle against evil, waged within every mind and heart, is one that must be waged and won for the Holy Spirit to become a part of our lives:
Only when a man has been cleansed from the shame of his evil, and has returned to his natural beauty, and the original form of the Royal Image has been restored in him, is it possible for him to approach the Paraclete.
Yet the Holy Spirit is never exhausted or diminished in His activity of illuminating and enlightening the souls of the faithful persons He descends upon:
He is distributed but does not change. He is shared, yet remains whole. Consider the analogy of the sunbeam: each person upon whom its kindly light falls rejoices as if the sun existed for him alone, yet it illumines land and sea, and is master of the atmosphere. In the same way, the Spirit is given to each one who receives Him as if He were the possession of that person alone, yet He sends forth sufficient grace to fill all the universe. Everything that partakes of His grace is filled with joy according to its capacity - the capacity of its nature, not of His power.
This is why at the beginning and the end of the day - and in our liturgical services - we call upon the Holy Spirit as the "Heavenly King, the Comforter, the Spirit of Truth," praying that He will "come and abide in us" in order to "cleanse us from every impurity and save our souls!"