While most of the Orthodox Christian world celebrates the Holy Protection, or Agia Skepi, of the Theotokos on October 1st according to ancient custom, Greeks celebrate the Holy Protection on October 28th as a special holiday in order to invite the secular government of Greece to honor the Theotokos for her special protection over the Greek people during World War 2.
The celebration of the Holy Protection dates back to 626 A.D., when the miraculous intervention of the Theotokos saved Constantinople from the Avars (Turkish-Mongolian Nomads), and it was officially established that October 1st be the date to honor this miracle. All Orthodox Christians celebrated this feast on October 1st until the 21st of October 1952 when the Holy Synod of the Church of Greece decreed (Συνοδικές Εγκύκλιοι, Τόμος Β', Αθήνα 1956, σελ. 649) that from henceforth there was to be celebrated in Greece a dual feast of the Holy Protection and the national holiday of "OXI" (pronounced "Ohi", which means "No), which commemorates Greek resistance to the Axis powers and freedom from the Italian and German occupation, on October 28th. A Service was specially written by Elder Gerasimos Mikragiannanites for this feast on October 28th.
On the first [or twenty-eighth] of this month [October], we celebrate the commemoration of the Holy Protection of our Most Holy Lady the Theotokos and Ever-Virgin Mary, namely her sacred Mantle cntained in the soros of the Holy Temple of Blachernae, when Saint Andrew the Fool for Christ beheld it spread out on high, and it covered all the faithful.
Verses for October 1st
All the faithful, pure one, you cover with your protection,
For you are our protection, and the salvation of the world.
On the first protect O pure one with your mantle those who sing your praises.
Verses for October 28th
You cover and comfort with your protection, O Pure One,
The faithful who look towards you, O Virgin.
The Protection of the Mother of God covers godly-minded Greece.
Once, during an all-night vigil that was being celebrated in the holy shrine in Blachernae, the blessed Andrew went there, as was his custom. Epiphanios was there also with one of his children. He would stand there, as was his custom was, because his fervor gave him strength, sometimes until midnight, sometimes until dawn. And so, when it was already about eleven o’clock at night, the blessed Andrew saw with his own eyes a most extraordinary vision coming in female form from the royal doors with a dread entourage, among which was the Honorable Forerunner and the Son of Thunder, holding her by the hand on either side, and many saints, robed in white, went before her; while others followed with hymns and spiritual songs. When she drew near the ambo, Andrew approached Epiphanios and said, "Do you see the Lady and Mistress of the world?" He replied, "Yes, my spiritual father."
And as they watched, she bowed her knees and prayed for a long time, shedding tears down her godlike and immaculate face. After her prayer, she advanced to the sanctuary, where she entreated for the people present. So when she had removed the mantle which she was wearing on her most-pure head and which had the appearance of lightning, she unrolled it and taking it with great reverence in her all-pure hands — it was large and awesome — spread it out above all the people who were standing there. The saints saw it stretched out over the people for a number of hours and blazing with the glory of the Lord like amber. As long as the Most Holy Theotokos was there, it was visible also, but after she had departed, it was no longer to be seen. For while she indeed took it with her, she felt behind her grace for those who were there.
At the prayers of your most pure Mother, Christ God, have mercy and protect us from visible and invisible enemies and save our souls. Amen.
Apolytikion in the First Tone
We sing hymns to the graces, of your Protection O Virgin, which like a bright cloud, is spread out beyond comprehension, and you cover your people noetically, from all the plots of the enemy. We have you as are our covering and protection and helper, and we cry to you: Glory to your magnificence Pure One, glory to your divine Protection, glory to your consideration for us, Immaculate One.
Another Apolytikion in Plagal of the Fourth Tone
Mother of God Ever-Virgin, you have given your holy Protection, through which you protect those who hope in you, as a mighty refuge for your race. For as of old so now you have wondrously saved us, enveloping your people like a spiritual cloud. And so we implore you to grant peace to your commonwealth, and to our souls God’s great mercy.
Kontakion in Plagal of the Fourth Tone
Like a cloud brightly overshadowing the whole company of the Church, O all-pure one, you appeared of old in the royal City. But as the Protection and Champion of your people, protect from every affliction us who cry to you: Rejoice, Protection wholly light.
Unfolding from on high your holy Protection, Virgin Mary, Mother of God, you protect and save your people, who cry out to you, Pure Maiden, hour by hour, while now they gratefully sing the praise of your wonders as they cry: Rejoice, Protection, wholly light!
Rejoice, gate of salvation.
Rejoice, protection of the Church.
Rejoice, wondrous vision of the Angels.
Rejoice, unshakeable support of mortals.
Rejoice, Ever-Virgin Mother of Christ the universal King.
Rejoice, protection and assistance of your faithful people.
Rejoice, for you appeared protecting your race.
Rejoice, for you grant victories to the troops.
Rejoice, source of abundant goodness.
Rejoice, lamp of God’s loving-kindness.
Rejoice, for through you we conquer the foe.
Rejoice, for to you we cry out each day:
Rejoice, Protection wholly light!
You are the Protection of Orthodox Christians, O Virgin, protecting all the faithful. And so your people take refuge in your Protection, and with faith magnifies your watchful care.