(EDITED) When does life begin according to the bible?

Emotional arguments are irregularly used as projectiles fired at range from the left and right side of the political isle regarding abortion and the right to life. But each argument hangs on the position about when life begins. Some say that life begins at conception, while other say that it begins the moment the head of the child breaches the vaginal canal, and there are a slew of definitions argued for in between.

Viability and the Point of Life

Before 1973, it was common law that if the baby was moving within the womb, an abortion was illegal, with some exceptions is specific states. The decision to legalize abortion was left to each individual state, until Roe vs. Wade overturned common law. They argued from the 14th Amendment that no one is to be “deprived of life, liberty, or property, without due process of law.” The trial spurred a slew of debates with one of them pertaining to the definition of life. It was common law prior to 1973 that life began when the baby began to “quicken”, or when movements of the baby could be discerned (16-25 weeks).[1] The ruling prevented states from regulating abortions during the first trimester.

Later in 1992, the Supreme court ruled on another case – Planned Parenthold vs. Casey – which differed in its ruling from Roe vs. Wade in allowing the state to regulate abortions in the first trimester. Life was redefined to the point of viability.[2] But since viability has to do with precise time at which a developing baby could survive outside its mother’s uterus, the point of viability varies from doctor to doctor and fetus to fetus. And this argument is wrought with legitimate concerns.

How should life be defined?

Christians are guilty of making the same emotionally-driven arguments as their presupposed counterparts. And so, an false dichotomy exists arbitrarily to represent the positions of the left and right. Life is defined at the physical separation of mother and baby for the pro-choice position, and life defined at conception for the pro-life position.

But, arguing that the bible is the ultimate authority for all precepts regarding faith and life, does God say anything regarding when life begins? If you’ve been so heavily distracted by the political conversation, you might be surprised that He does, indeed.

[Genesis 9:3-5, NASB] “Every moving thing that is alive shall be food for you; I give all to you, as I gave the green plant. Only you shall not eat flesh with its life, that is, its blood. Surely I will require your lifeblood; from every beast I will require it. And from every man, from every man’s brother I will require the life of man.”

[Leviticus 17:11, NASB] For the life of the flesh is in the blood, and I have given it to you on the altar to make atonement for your souls; for it is the blood by reason of the life that makes atonement.

Clearly, God, the Creator of life, said that the blood of every creature is what gives life. It is the reason why He imposed the Jewish sacrificial system in the Mosaic Law, and why ultimately Christ had to wrap Himself in flesh, take on the life of His creation, and die. The life is in the blood.

When does life start for a fetus?

If life is in the blood, then it would stand to reason that the moment that blood begins to enter the fetus, its begins its life. But, usually a mother and baby’s blood do not mix while the baby is in the womb.[3] The mother’s blood runs alongside the placenta, and the nutrients needed by the baby are absorbed and transferred to him/her. It is unnecessary that any blood whatsoever be given to the developing baby in the womb.

So when does a baby begin producing its own blood?

The heart of a baby begins beating at weeks 3 to 4.[4] The human heart, of course, is the organ responsible for pumping blood throughout the body via the circulatory system, supplying oxygen and nutrients to the tissues and removing carbon dioxide and other wastes.[5] (I can’t say that I understand this, but) during the first few weeks, before the heart begins to beat, hemangioblasts (precursor cells) differentiate into angioblasts, which give rise to the blood vessels and eventually forms the first elements of blood.[6] By day 16 the heart and blood vessels begin to form, and the heart begins to pump fluid through those vessels by day 20 with red blood cells appearing the next day; the end of week 3.

Therefore, if life of every creature, indeed, is in the blood – and it is because Scripture is explicit on that – then it should be argued that life begins at the end of week 3, or the beginning of week 4, at the very least.

Interestingly, women usually find out that they’re pregnant at 4-6 weeks. This is because most chemical tests look for the presence of hCG (human chorionic gonadotropin) in the blood or urine of the mother. This hormone is rapidly produced by the placenta shortly after implantation spurring many pregnancy symptoms.


We will be getting into the litany of arguments made by the pro-choice movement in contradiction to this argument in another post. But if you’re a Christian who believes that the bible is the ultimate rule for faith and life, you can have confidence in your answer that life is in the blood, and that, therefore, the life of a baby begins no later than week 4 – which is incidentally about the time that a mother can find out that she’s pregnant.


EDIT: After posting this article, it was argued from some that conception is still officially and biblically the beginning of life. It is possible that the blood of the mother to pass nutrients to the unborn baby should play a factor in whether the unborn baby developed less than four weeks should be considered alive. After all, the blood of Christ is from where we obtain eternal life – not from our own blood; transfusions from strangers can keep a patient alive. It is not far-fetched to argue that a mother’s blood passing nutrients to the fertilized egg constitutes life.


[1] McLaren, Reproductive Rituals , 188 n. 98; Williams, The Sanctity of Life and the Criminal Law , 149-152, 197. Web: Link

[2] Roe v. Wade, 410 U.S. 113 (1973). Web: Link

[3] Dr. Gerard M. Dileo (2014). Fetal Anatomy: Understanding Placenta Anatomy. Web: Link

[4] Yoder, PhD (2002). 3 to 4 Weeks | Prenatal Overview. Print.

[5] Children’s Hospital of Ph0iladelphia, The (2014). How the Normal Heart Works. Web: Link

[6] OpenStax College. (2013). Anatomy & physiology (Ch 20.6). Houston, TX: OpenStax CNX. Web: Link
*OpenStax College is an initiative of OpenStax CNX (formerly Connexions) at Rice University. Since 2012 OpenStax has created peer-reviewed open textbooks, which are available in both printed and digital formats. 

By |March 29th, 2018|blog|0 Comments

About the Author:

Aaron Gilmore is a Christian Apologist and is the founder and president of Bereans Aflame founded in 2014. He is husband and father to four children and serves diversely in his local church. Currently, he heads the IT Department at a Dallas-Fort Worth vocation center instructing students in IT certifications. He is a student at Lamar University in Texas studying for his B.S. in Communications. He plans to continue his education and attend Southern Evangelical Seminary for his Masters of Divinity in Apologetics, and ultimately his Doctorates in Philosophy.