In response to recent articles I’ve written in support of unborn babies and in opposition to abortion, one recurrent question has been, “How can you be so certain that an embryo or fetus is a human person with the same type of rights other humans have?” Although some readers are asking for scientific proof, most are looking for a theological rationale or saying that such a rationale cannot be found.

Fair enough. The Bible never states directly that “democratic republics should outlaw abortion” or that “the fetus is a person.” But it would be wrong to conclude that Scripture doesn’t provide good reasons to value unborn human beings as persons. In fact, both Scripture and the best of modern science infer that, from the time of conception, unborn human beings are persons created in the image and likeness of God.

In order to provide a very brief rationale for my view, I’ll begin by making clear that the Bible is pro-life, continue by showing that Scripture treats unborn human beings as persons, and conclude that personhood begins at fertilization rather than at some later point in the womb.

The Bible is Pro-Life

The Christian view of life and death is crystallized in the sixth commandment, “You shall not murder” (Exod 20:13).

Indeed, from beginning to end, Scripture reminds us that God is the creator, sustainer, and Lord of all life. He gave the “breath of life” to every creature (Genesis 1:30), including humanity (Gen 2:7). He endowed upon humanity a unique relationship to him as his image-bearers; human lives reflect something of our Maker’s own life.

When sin entered the world, so did death, but God in his mercy sent his Son to taste the full measure of death in our place, so that we might live eternally with him (Rom 6:2–4).

Because God takes pleasure in the life he has given, death grieves him. He expresses deep displeasure when one human being takes the life of an innocent other (Gen 4:10–11). The shedding of innocent blood offends him because it is an affront to God’s own image and the destruction of a person he created.

That’s why Jesus not only confirmed the sixth commandment, but deepened and extended it (Matt 5:21–26). Thus from cover to cover, the Bible affirms that human life is God’s good creation, whereas death is always an unwelcome intruder.

Unborn Human Beings are Persons

So, Scripture is clear that we should not take the life of another person created in God’s image and likeness. But do unborn human beings count as persons? Yes, they do.

Consider Jeremiah 1:5, where God says to the prophet, “Before I formed you I knew you; before you were born I sanctified you; I ordained you a prophet to the nations.” Here it is clear that God knew Jeremiah and related to him intimately as an unborn baby just as he would later when Jeremiah was an adult.

Similarly, Job 3:3, in which Job curses the day he was conceived and the day he was born. “May the day perish on which I was born, and the night in which it was said, ‘A male child is conceived.’” This passage employs a literary device known as synonymous parallelism, in which a passage of poetry states the same truth twice in a row, with the second statement affirming the truth of the first statement, but from a different angle. And in this passage, Job was cursing his personhood from conception through to birth.

Likewise, in Psalm 51:5, David communicates in nonscientific terms that he is interested in his own existence from the early days of existence in his mother’s womb. He uses “I” to refer to himself as an unborn human being.

Most significantly, consider Mary’s visit to Elizabeth just a few days after she learned of her pregnancy with Jesus (Luke 1:26-56). From the timeline given in the passage, Mary was most likely less than three weeks pregnant when Elizabeth calls her “the mother of my Lord” and when John the Baptist leapt in the womb at recognition of Jesus’ existence in the womb.

Many other passages similarly articulate the view that an unborn human being counts as a person and/or express sorrow over the loss of life before birth (e.g. Ex 23:26; Hos 9:14; Psalm 139:13-16).

This biblical teaching is confirmed by the best findings of modern science and attested by organizations such as  The American Association of Pro-Life Obstetricians and Gynecologists, an association of nearly 3,000 pro-life doctors.

Personhood Begins at Fertilization

So, Scripture refers to unborn human beings as persons. But at what stage in development does an embryo or a fetus become a person? At fertilization or at some other age of development along the way? Scripture and modern science give good reason to infer that an unborn human being becomes a person at the time of fertilization.

In making the case for fertilization as the starting point, I will follow closely David Van Drunen’s argument in Bioethics and the Christian Life. Van Drunen writes:

Fertilization is a unique and radical event. Before fertilization there is nothing recognizably identifiable as the human life that will develop into a full-grown human person. After fertilization, the embryo experiences an unbroken and continuous development, and at no point in that development does the embryo/fetus/child  undergo a radical transformation from one sort of being into another sort. (159)

What is so significant about fertilization? It is a one-day period during which the woman’s egg is penetrated by the man’s sperm. The two substances merge into a new forty-six chromosome substance called a zygote. Most importantly, the zygote is genetically different than both the egg and sperm. Neither the egg or sperm could develop into a human being on their own, but when transformed into a zygote, all of a sudden they can. The zygote represents a genetically new and unique being. A human being.

As we will see, no subsequent stage of development represents a radical transformation such as fertilization.


Does birth represent a radical transformation? No. Birth is an important event and yet it is not radically transformative. While a newly-born baby begins to breathe through her nose and receive nourishment through her mouth, and while she now becomes capable of independent existence, these changes are circumstantial rather than substantial. The baby has not changed significantly.


Does viability represent a radical transformation? No. The point of viability does not make a decisive change in the baby’s nature. Further, as science and medicine have developed, the point of viability has changed. In fact, because medical capabilities vary from era to era and context to context, there is no single point at which babies universally transform from being unviable to viable.


Does quickening represent a radical transformation? No. “Quickening” is a term used to refer to the moment in which a mother first feels her baby moving in the womb. While quickening represents a development in the life of the baby—he is moving vigorously enough for the mother to feel him in her womb—modern science makes clear that the fetus does not change decisively at this point.

Integration of Nervous System?

Does the maturation and integration of the baby’s nervous system represent a radical transformation? No. Theologically, we should not overemphasize rationality in relation to a human being’s dignity and value. Further, it’s questionable that the integration of the nervous system makes a baby “rational” in any sense of the world we normally use. While this stage sees the baby gains something new, it does not radically transform the baby.

Third Week?

Does the third week represent a radical transformation? No, but this stage of development is the strongest challenger to the “fertilization” view for which I am arguing. Some thinkers argue that the third week represents a time during which a living human entity becomes an individual human life.

Proponents of this view note, for example, that during the first three days, the mother’s “messenger RNA” helps the baby’s genes to begin developing (and in their view, this external assistance means that the baby is not yet an individual). But this example is unconvincing: why does the external influence of the mother’s RNA negate the individuality of the baby?

Similarly, they note that during the embryo’s first few days of existence, each of its cells has the potential to develop into numerous different kinds of human cells. But this example is unconvincing: of course various parts (cells) of the baby could develop in various directions if disconnected from the whole (the baby), but the parts remain connected to the whole and thus are part of the baby’s development as a human person.

Finally, proponents of this view note that twinning happens after fertilization. However, even this challenging argument shouldn’t sway us from the fertilization view. Most embryos do not twin. And even those who do are a mystery to us. Scientists do not know why some embryos twin—whether the twinning is caused by internal or external forces. Neither do they know the exact relationship of the twin embryos to the single embryo from which they emerged.

The twinning scenario is the most challenging aspect of the “third week” argument, and yet it does not prove that the baby is not an individual during the first three weeks.


After evaluating other points of development, we conclude that fertilization is the point at which an unborn human being becomes a person. Van Drunen is worth quoting at length:

The final conclusion, therefore, is that modern scientific learning shows fertilization to be a unique event in which a new kind of living being comes into existence. If Scripture compels us to conclude that human beings are image bearers of God from their earliest days, and if science asks us when exactly that identity is established, the evidence that science provides suggests that the answer to that question must be fertilization. (165)

Protected in Law, Welcomed in Life

As Christians, we should neither weary nor rest until our nation rectifies its greatest legalized injustice, its denial of liberty and equality to an entire class of people—unborn human persons.

Neither should we neglect to highlight God’s grace toward any person who has taken part in any sin—including abortion. Toward abortive mothers, God offers his Son to liberate them from residual guilt; to fathers who approved of, paid for, or pressured an abortion, God offers himself as a Father whose Son was killed to set them free; to medical personnel who assist in abortions, God offers himself as the Great Physician who offers eternal life to those who have caused temporal death. Just as God has extended his grace to me—a great sinner—so he offers grace to those who have committed abortive sins.

Thus, let us each play our role in seeking legal reform and spiritual and social renewal, so that every unborn American person—from fertilization until birth—is protected in law and welcomed in life.

Resources for Further Reflection

A discussion of this gravity deserves more time and attention than can be paid in a single blog post. For further reflection, consider these resources:


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