The most Blessed Virgin Mary was, from the first moment of her conception, by a singular grace and privilege of almighty God and by virtue of the merits of Jesus Christ, Saviour of the human race, preserved immune from all stain of original sin. 135
Catechism number 506
Mary is a virgin because her virginity is the sign of her faith "unadulterated by any doubt", and of her undivided gift of herself to God's will.168 It is her faith that enables her to become the mother of the Saviour: "Mary is more blessed because she embraces faith in Christ than because she conceives the flesh of Christ."169