The most important church in the city of Rome dedicated to Our Lady is the Basilica of Saint Mary Major, erected around the year 352, during the reign of Pope Liberius. (352-366) According to legend, a member of an aristocratic family, John and his wife were childless and prayed that the Blessed Mother might designate an heir to bequeath their wealth. They were favored with a dream in which Our Lady appeared to them on the night of August 4-5. She requested that they build a church in her honor on the Esquiline hill and the sign to accompany this dream is that the exact location would be marked out in snow.
During that hot summer evening, a miraculous snowfall traced the form of the basilica on the hill. Our Lady also appeared to Pope Liberius in a dream that same night so that he too could arrive at the location to see the miraculous snowfall. Many people gathered to see the unusual event of snow glistening in the August sun. Upon awakening, John and his wife rushed to the site and Pope Liberius arrived in solemn procession.
Realizing that the snow marked the exact location of the church, the people staked off the area before the snow melted. The basilica was completed within two years and consecrated by Pope Liberius; that is why it is sometimes referred to as the Basilica Liberiana, after the Pope who consecrated it.
The liturgical feast of the Dedication of the Basilica of St. Mary Major is celebrated each year on the fifth of August. On that day, a beautiful custom is kept each year in which a shower of white rose petals are dropped from the ceiling to commemorate the miraculous snowfall.
On the 5th day of August, which is that time when the heat of summer waxeth greatest in Rome, a part of the Esquiline Hill was covered by night with snow. And on this same night the Mother of God appeared in a dream to John and his wife separately, and told them that on that spot, which in the morning they should see clad with snow, they should build a Church, to be dedicated in the name of the Virgin Mary, for that this was the way in which she chose that they should make her their heiress. John went and told it to Pope Liberius, who declared that he also had been visited by a like dream.
V. But thou, O Lord, have mercy upon us. R. Thanks be to God.