Any act would not be any good if it were not perhaps for a divine endowment, which we is called grace, on it.  With the sufficiency of grace, any just man is able to perform meritorious acts that lead him to eternal life.

Grace, of course, is not a product of any human exercise. It is grace precisely, because it is a gift, a very special gift. In the Trinitarian life of God springs forth love. A love which is generous, a love which is overflowing reaches out to humankind in order to share God’s own life.

That same love prompted God the Father to send His only Son so as to save the humanity from the damnation of sin. And so in the fullness of time, the Word of God became flesh. The Son of God became part of the humanity He was to redeem, being born of a woman, who herself was destined from all eternity to be the worthy vessel of the Creator. The woman’s name was Mary. And she was the worthy Mother of the Redeemer because she was Full of Grace.

In the mystery of Christ, Mary is present even before the creation of the world, as the one whom the Father has chosen to be the Mother of His Son in the Incarnation. Mary is Full of Grace because it is precisely in her that the Incarnation of the Word is accomplished and fulfilled.

In the fullness of grace, there is such thing as the absolute fullness which is about the grace that exists in Christ, the Savior of the world. St. Paul speaks of this in his letter to the Ephesians: The glory of grace that God the Father… has bestowed upon us in His beloved Son. In Him we have redemption through His blood. (1:7) However, Mary being the mother of the redeemer shares in that fullness of grace in a very sublime manner. By virtue of the richness of the grace of the beloved Son, by reason of the redemptive merits of Him who willed to become her Son, Mary was preserved from the inheritance of original sin.[1]

In an entirely special and exceptional way, Mary is united with Christ, and similarly she is eternally loved in this beloved Son, this Son Who is one with the Father and in whom is concentrated all the glory of grace.[2]  Mary then is full of grace because she stays perfectly open to this gift from on high.