The Ancient Question That Modern Medicine Has Resurrected
The question of when human life truly begins has haunted philosophers, theologians, and lawmakers for millennia. Now, modern medicine has pushed this ancient debate into the spotlight once again. With groundbreaking advances in embryology, prenatal diagnosis, and reproductive technology, the stakes have never been higher.
A comprehensive new study published in the journal Religions offers a fascinating comparison of how two of the world’s oldest monotheistic traditions—Islam and Judaism—approach this profound question . The research, conducted by scholars from Bolu Abant Izzet Baysal University in Türkiye, reveals a complex tapestry of shared values and stark differences that continue to shape the lives of millions of believers worldwide.
Both religious traditions regard the developing fetus as a form of human life worthy of protection. Yet they diverge significantly regarding when that life attains full moral and legal status. These distinctions lead to dramatically different legal outcomes on issues like abortion, maternal health emergencies, and fetal abnormalities .
The Islamic Perspective: A Gradual Journey Toward Personhood
Islamic law, or Shariah, envisions human development in the womb as a step-by-step process, with each stage carrying distinct legal implications. The foundational texts—the Qur’an and Hadith—describe this journey in remarkable detail.
According to Islamic tradition, human creation unfolds through specific phases: nuṭfah (a drop of fluid), ʿalaqah (a clinging clot), muḍghah (a chewed-like lump of flesh), followed by bone formation and the clothing of bones with flesh. The pivotal moment arrives with nafkh al-rūḥ—the breathing of the soul into the developing fetus .
A well-known saying of Prophet Muhammad (peace be upon him) establishes a 120-day timeline for this process. For the first forty days, the embryo exists as a drop; for the next forty, as a clinging clot; for the final forty, as a lump of flesh. Then an angel is sent, and the soul is breathed into it .
This timeline has profound legal consequences. However, Islamic scholars are far from unified in their interpretations:
- Hanafi scholars hold three distinct positions: Some prohibit abortion from conception; others allow it up to 120 days; still others restrict permission to the first 40 days .
- Maliki jurists generally prohibit abortion from the fortieth day onward, treating the fertilized egg with the same legal consideration as a developing fetus once it has the potential to progress .
- Shafi’i and Hanbali schools show similar diversity, with some allowing abortion within the first 40 days and others extending the window to 120 days .
Contemporary Islamic jurists have engaged with modern medical knowledge, leading to new perspectives. Some scholars now argue that human life begins at fertilization and therefore prohibit abortion from the very start. Others maintain the traditional view that ensoulment at 120 days is the decisive threshold.
Where Islamic scholars find consensus is in cases where the mother’s life is in grave danger. In such circumstances, abortion is permitted—and sometimes even required—based on the legal principle of “choosing the lesser of two evils” .
Key Islamic Rulings on Abortion by Gestational Stage
| Stage of Pregnancy | Islamic Legal Status | Permissibility |
|---|---|---|
| First 40 days (pre-ensoulment) | Embryo considered “drop” (nutfah); variable views across schools | Generally permitted by some Hanafi and Shafi’i scholars under conditions; considered makruh (disliked) by others |
| 40 to 120 days (pre-ensoulment) | Fetus in development stages (alaqah, mudghah) | More restrictive; permitted only for serious reasons (maternal health risk, fetal abnormalities, rape) by some scholars |
| After 120 days (post-ensoulment) | Fetus has received soul; full human status | Universally prohibited except to save mother’s life, as this is considered unlawful killing |
| Maternal life endangerment | All stages | Permitted and often obligatory; mother’s certain, existing life takes precedence over potential life |
The Jewish Perspective: Birth as the Defining Threshold
Jewish law, or Halakha, takes a notably different approach. While the fetus is accorded significant moral value, full legal personhood is generally associated with birth rather than conception or ensoulment .
The foundational text for this understanding comes from Exodus 21:22–23, which describes a scenario where a pregnant woman is injured and miscarries. If no further harm occurs, the offender pays financial compensation. However, if the woman dies, the principle of “life for life” applies. Jewish legal tradition interprets this distinction as indicating a difference in legal status between a fetus and a born human being .
Rabbinic literature further elaborates this perspective. During the first forty days after conception, the Talmud describes the embryo as maya be-alma—”mere water” [citation:15]. From the forty-first day onward, the fetus occupies an intermediate stage of development. However, a pregnancy is not regarded as fully established until approximately the third month.
The fetus is not considered an independent nefesh (living soul) until birth. Nevertheless, Jewish law does not treat the fetus as a mere biological entity. It holds significant moral weight as a developing human life with the potential to become a full person [citation:16].
This intermediate status creates a nuanced legal framework. In the Mishnah Ohalot 7:6, a clear principle emerges: if a woman’s life is threatened during childbirth, the fetus may be dismembered and removed to save her. The mother’s actual and existing life takes precedence over the fetus’s potential life [citation:17]. However, once the fetus’s head has emerged, it is considered an independent life, and intervention is no longer permitted—even to save the mother.
Rabbinic authorities have developed this principle further. Maimonides, the great medieval Jewish scholar, classified a fetus endangering the mother as a rodef (a “pursuer”)—someone who poses a lethal threat—and therefore one who may be stopped, even at the cost of their life [citation:18]. This principle has shaped Jewish law’s approach to therapeutic abortion for centuries.
Key Jewish Legal Perspectives on Fetal Status by Stage
| Stage of Pregnancy | Jewish Legal Status | Legal Implications |
|---|---|---|
| First 40 days | Fetus considered “mere water” (maya be-alma) | Greatest leniency; abortion permitted in cases of great need; fetus not considered significant for legal purposes |
| 41 days to birth | Fetus as developing life; has organs and form but not yet a nefesh | Entitled to moral and legal protection; abortion generally prohibited except for serious reasons |
| Mother’s life endangered | All stages | Abortion permitted—and sometimes obligatory; fetus treated as rodef (“pursuer”) |
| During active labor | Before head emerges: potential life; after head emerges: full person | Before emergence: may be dismembered to save mother; after emergence: cannot be harmed |
| At birth | Full legal personhood (nefesh) | Complete independent legal status and rights |
Where the Traditions Converge and Diverge
Despite their different starting points, Islamic and Jewish legal traditions share remarkable common ground [citation:19][citation:20]:
Protection of Potential Life. Neither tradition regards the fetus as a mere clump of cells without value. Both recognize it as a developing form of human life worthy of protection and respect.
Gradual Legal Status. Both traditions evaluate fetal status on a sliding scale. The earlier the pregnancy, the greater the legal flexibility. As the fetus develops, protections increase.
Maternal Priority. When the mother’s life is in serious danger, both traditions prioritize her survival. This principle stands firm regardless of the stage of pregnancy.
Yet significant differences remain:
The Decisive Threshold. For most Islamic scholars, ensoulment at 120 days marks the transition to full human status. In Jewish law, this threshold is birth itself.
Fetal Independence. In Jewish thought, the fetus is generally considered part of the mother’s body until birth. Islamic tradition grants the fetus a more independent status from the moment of conception.
Reasoning and Framework. Jewish law develops its positions through continuous rabbinic interpretation and debate. Islamic law relies more heavily on scriptural texts and the consensus of scholars.
Mental Health Considerations. Contemporary Jewish authorities have increasingly considered maternal mental health as a valid justification for abortion. In Islamic jurisprudence, mental health arguments are gaining ground but remain less widely accepted [citation:21].
What Modern Medicine Tells Us
Contemporary embryology reveals that human development is a continuous process beginning at fertilization. A genetically distinct human organism develops from the moment of conception. Medical science calculates gestational age from the last menstrual period, with actual development from fertilization taking approximately 38 weeks [citation:22][citation:23].
This scientific framework helps us better understand the 40-day and 120-day thresholds found in classical texts. However, biology alone cannot resolve the normative question of when legal personhood or moral status should be recognized [citation:24]. That remains a matter of religious interpretation, ethical reasoning, and legal deliberation.
The Bottom Line
The study of these two great religious traditions reveals that the question of when human life begins is not simply a matter of biology. It involves profound questions about personhood, moral status, legal protection, and the relationship between mother and child. Both Islam and Judaism offer rich intellectual frameworks for addressing these questions, frameworks that continue to evolve in response to medical advances and contemporary challenges.
Perhaps most remarkably, both traditions demonstrate that it is possible to hold strong convictions about the value of fetal life while recognizing legitimate exceptions. This nuanced, case-by-case approach stands in stark contrast to the polarizing absolutism that often characterizes public debate on abortion.
Understanding these traditions—their complexities, their diversities, and their shared values—offers a model for how we might approach this deeply personal and profoundly important question with greater wisdom and compassion.
Summary
A new study comparing Islamic and Jewish legal traditions reveals nuanced positions on when human life begins and the permissibility of abortion. Both religions view the developing fetus as worthy of protection but differ on when full legal and moral status attaches. In Islamic law, ensoulment at 120 days of pregnancy is widely considered the decisive threshold, with varying opinions on abortion before that point. Hanafi scholars hold three different positions—prohibiting abortion from conception, allowing it up to 120 days, or restricting it to the first 40 days. Maliki jurists generally prohibit abortion from day 40 onward. Jewish law, by contrast, associates full legal personhood with birth, describing the embryo as “mere water” during the first 40 days and not recognizing it as an independent nefesh until delivery. Both traditions prioritize the mother’s life when endangered: Islamic law permits abortion based on the principle of “choosing the lesser of two evils,” while Jewish law classifies a threatening fetus as a rodef (“pursuer”) who may be stopped. Contemporary developments include growing consideration of maternal mental health and fetal abnormalities, with some authorities now permitting abortion in such cases. The traditions demonstrate remarkable diversity within their own frameworks, with multiple authoritative opinions coexisting. Neither tradition is monolithic, and both offer flexible, nuanced approaches that balance the protection of fetal life with the preservation of the mother’s health and well-being.
Reference: Yiğitoğlu, M.; Yiğitoğlu, M. Defining the Beginning of Human Life: Embryo Status and Abortion in Islamic and Jewish Legal Traditions. Religions 2026, 17, 984. https://doi.org/10.3390/rel17080984
