O Sanctissima is a prayer written in the 18th century, but the song set to the prayer is still vastly popular today. The author, who is unknown, dedicated these beautiful verses to the Virgin. The text recalls the holiness, purity, and sweetness of Our Lady. It references the Immaculate Conception and underscores the beautify of the Blessed Virgin. The first two lines are also a clear allusion to Song of Songs.
We can meditate on this small masterpiece with the words of St. Louis de Montfort, which are found in his True Devotion to Mary: “The saints have said wonderful things of Mary, the holy City of God, and, as they themselves admit, they were never more eloquent and more pleased than when they spoke of her. And yet they maintain that the height of her merits rising up to the throne of the Godhead cannot be perceived; the breadth of her love which is wider than the earth cannot be measured; the greatness of the power which she wields over one who is God cannot be conceived; and the depths of her profound humility and all her virtues and graces cannot be sounded. What incomprehensible height! What indescribable breadth! What immeasurable greatness! What an impenetrable abyss!”