Here are six reasons I feel so certain (I explore these and others in my book The Marian Option: God’s Solution to a Civilization in Crisis):
See John Paul II’s reflections on this in Gift and Mystery.
1) Catholics don’t worship Mary
To put Protestants at ease right way: Catholics do not worship Mary. Period. We venerate her because as the Mother of Jesus, Christ came to us through her. God could have done it any way he wanted, and yet this was how he chose to come to us. It is only fitting then, that the Mother should help us return to her Son. Protestants are comfortable with venerating St. Paul, for example, speaking of him highly, recommending that others get to know his work. Similarly Catholics revere Mary. She is clearly not God, but a creature given incredible graces and gifts by the Creator.
2) Love isn’t binary
There seems to be a sense that if we love Mary, then we must not love Jesus as much as we could or should – that somehow loving the Mother takes away from the Son. But family relationships aren’t binary. What son resents that his friends love his mother? What good mother feels slighted because her children love their father, too? In a family, love is abundant and overflowing.
3) Jesus isn’t jealous of His mother
In a poetic moment, Pope Paul VI wrote, “The sun will never be dimmed by the light of the moon.” Jesus, as the Son of God, doesn’t feel threatened by love and devotion to his Mother. He trusts her and loves her and knows their wills are united. Mary, because she is a creature and not the Creator, will never outshine the Trinity, but always be a reflection of it.
4) She is our Mom
Whether we know it or not, Mary is our spiritual Mother. That moment on the Cross, when Christ gives Mary to St. John, and St. John to his Mother, is when Mary’s role as mother expands to all of humanity. She is closest to those who will stand with her at the foot of the Cross, but her love is not limited just to Christians. She knows well what it cost her Son to purchase our salvation. She doesn’t want to see it squandered.
5) Like a good mom, she makes everything better
Recently, a Protestant challenged my appeal to Mary for assistance in our troubled times by suggesting that devotion to her was solely interior, with little regard for the active life. What is largely misunderstood about Mary is how she transforms our active life. When praying with Mary, not only do we draw closer to her and her Son, but our unique personal mission can be revealed, energized, and transformed by her intercession.
6) You can know a tree by its fruit
Scripture speaks of knowing a tree by its fruit (cf. Matthew 7:16). There is abundant fruit when we look at what Mary has done for the Church historically, geopoliticly, and culturally. Not only has she stopped famines, wars, heresies, and persecutions, but she has inspired artists and thinkers at the pinnacle of culture – Mozart, Botticelli, Michelangelo, St. Albert the Great, and the master builders who erected Notre Dame Cathedral, just to name a few.
The testimonies of the saints are overwhelming when it comes to just how powerful her intercession is. There are abundant numbers of canonized saints who spoke highly of her, but you will never find one that spoke poorly of her. Cardinal John Henry Newman noticed that when Mary is abandoned, it isn’t long before a true practice of the faith is abandoned as well.