When I wrote Mary: A Catholic-Evangelical Debate with an old friend from Bob Jones University, I had difficulty explaining the real unity Catholics have always sensed between Jesus and his mother.

Recently, it occurred to me that I should have been more biological in my apologetics. An item on the morning news sparked the idea.

Researchers into fetal-cell behavior have discovered that when a woman is pregnant, fetal cells proliferate within her body. In simple terms, primitive fetal cells from her baby remain within her system.

Furthermore, some scientists believe these cells migrate around the mother’s body and mysteriously help to heal her through their natural generative abilities. They did a liver biopsy on a woman with hepatitis, and discovered that her liver was covered with hundreds of fetal cells. It was as if the fetal cells had gone to the liver to help fight off the disease. If it’s true, it’s an exciting and beautiful discovery that hammers home the truth we already knew — that there are mysterious and life-giving links between a mother and her children.

In the case of Jesus and the Virgin Mary, this means that from his conception onward, cells from Jesus must have remained within Mary. Just as he physically came from her, so he physically remained with her. He was a part of her, and she was a part of him. In our individualistic age, we have trouble imagining that invisible links exist between us and our family members, but the biology seems to support what the spiritual directors and psychologists have known for a long time: that all of us are members of one body.

In the relationship between Mary and Jesus we see the essential interdependence of man and woman in God’s plan. St. Paul writes about this mystery when he says, “For man did not come from woman, but woman from man; neither was man created for woman, but woman for man. … In the Lord, however, woman is not independent of man, nor is man independent of woman. For as woman came from man, so also man is born of woman” (1 Corinthians 11).

If the physical body of Christ came from Mary and remained with Mary, the same is true of the precious blood.

St. Elizabeth Ann Seton came to accept and love this mystery through her own experience of motherhood. She contemplated the fact that the infant Christ was nurtured at the breast of Mary, and echoes the Church fathers who also contemplated the mystery that the blood of Christ that would redeem the world came first from the blood of his mother through her milk. Now that we know more about fetal development, we can see that this connection is even more profound and literal.

In the womb, Jesus would have been literally nourished through Mary’s bloodstream. Furthermore, if he took his human nature from her, then not only was his genetic make-up 100% Mary’s, but also the blood that he shed for the salvation of the world was her blood. When Simeon prophesied to her, “a sword shall pierce your own heart also,” it was more amazingly and profoundly true than he could ever have imagined.

If the cells of Jesus remained within Mary’s body and his blood was her blood, then biologically speaking, it is impossible to venerate the precious body and blood of Our Lord without also venerating Mary’s contribution.

When my evangelical friends sing heartily, “There is power, power, wonder working power in the precious blood of the Lamb,” we Catholics should be able to sing with them. As we do, we are brought more deeply into the mystery of Mary’s cooperation in her son’s work of redemption. When we go to Mass and receive the body and blood of Our Lord, it is right and fitting that the image of Mary is always there at the side, as a reminder of her part in our redemption

How does this affect apologetics with evangelicals? Firstly, we can build on the positive fact that evangelicals really do believe in the Virgin Birth and the Incarnation. From this positive affirmation they will usually admit that Mary was not just a channel or conduit for God’s Son to come into the world. With us they affirm Galatians 4:4 that says God’s Son was born of a woman, not through a woman.

From there it is interesting to ask what the implications of this fact are. If they believe in the Incarnation, then non-Catholic Christians must admit that Jesus’ body and Mary’s body are united more closely than any other mother and son, and that his body came from her body, and that his blood was her blood; and if the recent research is true, then his body stayed within her body and his blood remained her blood.

These biological facts have theological implications. Not only do they reinforce the intimate bond between Jesus and Mary, but they also serve as an excellent picture of how Jesus and Mary are related and interdependent. Just as he took his body and blood from her, so she continues to support and donate herself to him. As he suffered, she suffered.

As his blood was shed, it was also her blood that was shed. As his heart was pierced by the spear, hers is also pierced by a sword of sympathetic suffering. As his cells remained in her body, so his life also remained in her. That’s why she shares in his resurrection when she is assumed into heaven, and shares his glory when she is crowned in heaven. The biological facts illustrate and consolidate what Catholics have always held by faith in the doctrinal tradition.

These biological facts also have personal implications. A fresh understanding of the intimate bond between Jesus and Mary should spark our love and devotion to the Blessed Virgin, and through this maternal love we will be drawn ever closer to the focus and direction of her whole life: her son, our only Savior and Master, Jesus Christ.

Dwight Longenecker’s

book, Mary: A Catholic-Evangelical Debate is available from

DwightLongenecker.com.