Solemnity of the Immaculate Conception

“Hail Mary, full of grace”. For thousands of years, millions of times per day the Virgin Mary is greeted by the faithful with the greeting of the Archangel. The sons of the Church learn from the words of the Archangel Gabriel that the fullness of the mystery of God’s grace was realized in Holy Mary. St. Paul the Apostle teaches us that the Father made all fullness dwell in His Incarnate Son (c.f. Col 1:12-20), which overflows from Christ’s head and spills out on His Mystical Body that is the Church. Before descending in Body, Christ’s fullness was spread in a unique and unrepeatable way on Mary, predestined from eternity to be the Mother of God.
https://www.catholicculture.org/culture/liturgicalyear/calendar/day.cfm?date=2015-12-08