It is therefore certain that Jesus is the fruit and gift of Mary for every single man who possesses him, just as truly as he is for all mankind.
Consequently, if any of the faithful have Jesus formed in their heart they can boldly say, “It is thanks to Mary that what I possess is Jesus her fruit, and without her I would not have him.”
We can attribute more truly to her what Saint Paul said of himself, “I am in labour again with all the children of God until Jesus Christ, my Son, is formed in them to the fullness of his age.”
God the Holy Spirit wishes to fashion his chosen ones in and through Mary. He tells her, “My well-beloved, my spouse, let all your virtues take root in my chosen ones that they may grow from strength to strength and from grace to grace.
“When you were living on earth, practising the most sublime virtues, I was so pleased with you that I still desire to find you on earth without your ceasing to be in heaven.
“Reproduce yourself then in my chosen ones, so that I may have the joy of seeing in them the roots of your invincible faith, profound humility, total mortification, sublime prayer, ardent charity, your firm hope and all your virtues.
“You are always my spouse, as faithful, pure, and fruitful as ever. May your faith give me believers; your purity, virgins; your fruitfulness, elect and living temples.”
When Mary has taken root in a soul she produces in it wonders of grace which only she can produce; for she alone is the fruitful virgin who never had and never will have her equal in purity and fruitfulness.
[...] When the Holy Spirit, her spouse, finds Mary in a soul, he hastens there and enters fully into it. He gives himself generously to that soul according to the place it has given to his spouse.
One of the main reasons why the Holy Spirit does not work striking wonders in souls is that he fails to find in them a sufficiently close union with his faithful and inseparable spouse.
I say “inseparable spouse”, for from the moment the substantial love of the Father and the Son espoused Mary to form Jesus, the head of the elect, and Jesus in the elect, he has never disowned her, for she has always been faithful and fruitful.
Louis de Montfort (1673-1716): True Devotion to the Blessed Virgin, 33-36.