Intercession of the Theotokos

The Intercession of the Theotokos or the Protection of Our Most Holy Lady Theotokos and Ever-Virgin Mary, known in Church Slavonic as Pokrov (Покровъ, "protection"), and in Greek as Sképē (Σκέπη), is a feast of the Mother of God celebrated in the Eastern Orthodox and Byzantine Catholic Churches. The feast celebrates the protection afforded the faithful through the intercessions of the Theotokos (lit. Mother of God, the Eastern version of the Virgin Mary). In the Slavic Orthodox Churches it is celebrated as the most important solemnity besides the Twelve Great Feasts. The feast is commemorated in Eastern Orthodoxy as a whole, but by no means as fervently as it is in Russia, Belarus and Ukraine.

The Slavic word Pokrov, like the Greek Skepê has a complex meaning. First of all, it refers to a cloak or shroud, but it also means protection or intercession. For this reason, the name of the feast is variously translated as the Veil of Our Lady, the Protecting Veil of the Theotokos, the Protection of the Theotokos, or the Intercession of the Theotokos. It is often translated as Feast of the Intercession or Feast of the Holy Protectress.

With some reservations, the Pokrov icon may be related to the Western Virgin of Mercy image, in which the Virgin spreads wide her cloak to cover and protect a group of kneeling supplicants (first known from Italy at about 1280).

According to Eastern Orthodox Sacred Tradition, the apparition of Mary the Theotokos occurred during the 10th century at the Blachernae church in Constantinople (modern-day Istanbul) where several of her relics (her robe, veil, and part of her belt) were kept. On Sunday, October 1 at four in the morning, St. Andrew the Blessed Fool-for-Christ, who was a Slav by birth, saw the dome of the church open and the Virgin Mary enter, moving in the air above him, glowing and surrounded by angels and saints. She knelt and prayed with tears for all faithful Christians in the world. The Virgin Mary asked Her Son, Jesus Christ, to accept the prayers of all the people entreating Him and looking for Her protection. Once Her prayer was completed, She walked to the altar and continued to pray. Afterwards, She spread Her veil over all the people in the church as a protection.

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Wikipedia