Dear Mary:

Sorry I am a little late in answering.

It is true that our Blessed Mother was Full of Grace and by virtue of her Immaculate Conception was freed from original sin and concupiscence that comes with it. This means that she was sinless.

The Pentecostal decent of the Holy Spirit involved two primary experiences:

1) it was a prophecy that the Holy Spirit would be given to the the faithful. In Old Testament times people were filled by the Holy Spirit only at certain times and other times they were not. This is like most of us. Few of us are filled with the Spirit all the time. But, there can be moments when the Holy Spirit fills us and empowers us to do or say things that we never would. But, in Old Testament times, it was not just a matter of temporary filling of an individual, the presence of the Holy Spirit was not on the earth except during those times with some prophet or other person was temporarily filled by the Spirit.

Thus, the Holy Spirit's access to the earth was limited. Adam and Eve, in essence, handed over to the devil the deed of the planet. The earth was his domain. The Cross and Resurrection not only defeated death and sin, but with the decent of the Holy Spirit, God re-occupied the earth, took back the deed from the devil. What Adam and Eve lost, Jesus and Mary regained. Thus, descent of the Holy Spirit at Pentecost was a return of the Spirit of God to the earth permanently until the end of time. The Holy Spirit is now present all the time within all baptized persons, even if not always filled totally.

This descent of the Holy Spirit not only appropriated the deed of the earth, and was a gift to each baptized person, but is also a gift to the Church to protect her and guide her through the Pope and Magisterium.

2) Although Mary was already filled with the Spirit, the Apostles were not. On Pentecost they were filled with the Spirit and by that were emboldened to proclaim the Gospel and to even die for Christ.

While Mary was already filled with the Holy Spirit, I imagine the descent of the Holy Spirit on Pentecost gave her new gifts, excitement, and enthusiasm. The Blessed Mother, being the mother of us all, I am sure swelled with joy to see the Apostles receive the Holy Spirit for the first time in this way and further to be filled with the Spirit and so on-fire for her Son.

Anyway, those are my thoughts.

God Bless,
Bro. Ignatius Mary