Seven is a number that expresses completeness in the Bible. God creates the world in seven days. The construction of the temple in Jerusalem is completed in seven years. Inside the temple liturgy, the priest sprinkles blood seven times for complete forgiveness.
Revelations came to John after each of the seven seals was opened by the Lamb. The revelation of the seventh seal was the blowing of seven angelic trumpets with seven concomitant revelations. The revelation of the seventh trumpet of the seventh seal was thus the seven of sevens, a completion of completion, a satisfaction of satisfaction, and a holy of holies. It was then that John saw the opening of the temple and a showing forth of its contents never seen by the people, due to its sacred nature. Heaven was opened, and a pregnant woman was seen there, clothed with the sun, with the moon under her feet and a crown of twelve stars.
The Church sees in this revelation an indirect reference to the Blessed Virgin Mary giving birth to the Christ child. Our Lady participated in the seventh seven, in the completion of all completion. Her entire life flowed from her perfect completion of God’s will, from beginning to end, and it was a very unique end, indeed. It was unique in holiness and glory, and so it is celebrated by the Church today. May St. Mary, assumed into heaven, intercede for all those who love her and seek the company of her Son.