Catholics believe that Mary was conceived without sin; but do they also believe that Mary was sinless throughout her entire life? This is a question posed to me by a Protestant who believes Mary was a sinner.
The Church teaches that “In consequence of a Special Privilege of Grace from God, Mary was free from every personal sin during her whole life.
The Council of Trent declared: No justified person can for his whole life avoid all sins, even venial sins, except on the ground of a special privilege from God such as the Church holds was given to the Blessed Virgin.
Pope Pius XII says in the Encyclical Mystici Corporis: of the Virgin Mother of God, that: “she was immune from all sin, personal or inherited” (pg. 203 *Fundamentals of Catholic Dogma * by Ludwig Ott).
Mary’s sinlessness is rooted in Luke 1:28: “Hail, full of grace”. …” Moral defects are irreconcilable with fullness of grace.” (ibid).
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