What does the Bible and Science have to say about Gender, Sex, and Marriage?

Watch our new video to find out

Note: the footnotes have been omitted below—see the video and downloadable book below for sources used.

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Does modern science validate what the Bible says about gender, sex, and marriage? Does living under the Bible’s idea on these topics make an impact on our lives? Our marriages? Our children? Watch our video (above) to the end to find out.

But first, a disclaimer. We want to remind our viewers that—from the Bible’s perspective—we live in a fallen world. The effects of Adam and Eve’s sin continue driving humanity against God’s initial blueprint for men, women, sex, marriage, and life. We all know the long list of sexual sins laid out in the Bible.  We’ve all been impacted by divorce in one way or the other. We’ve all sinned sexually in one way or the other. Many today have been trapped into traveling long journeys away from God’s blueprint in ways that will not allow their legacy on earth to continue. Fortunately, God’s forgiveness and grace can redeem and heal us, and put us on track for restoration, but this requires repentance, which means turning away from our sins. Like the woman caught in adultery, Jesus forgives her, then says, “Go and sin no more.” It also means giving the rest of our lives to Christ, asking Him to take over, and living under what God’s Word says on these topics.

Before we dive in, let’s start with a quick review of the Bible’s take on these topics, going all the way back to the beginning. After God forms the earth and fills it with life, he creates a pair of stewards to take care of everything. He starts with Adam, drawing him from dust of the ground and breathing life into his nostrils. There was no man before him, and no population of apes from which he evolved. As a mark of rule over the animal kingdom, God charged Adam with naming all the earth’s creatures.

Then, knowing that man was incomplete and it was not good for him to be alone, God said: “I will make him a helper comparable to him.” The Hebrew carries the idea of God making a “a helpmate opposite him” or “as in front of him,” describing an individual who is both like a man in terms of being human, but who is also an opposite or complement to the man by being that which is formed from him.” Man was only half the story without woman. She was not some afterthought or servant created to help an independent, self-sufficient man. Rather, God said Adam’s condition without Eve was “not good.” This is why Genesis later states that “God created them male and female, and blessed them and called them Mankind…” Even Adam knew this by exclaiming after Eve was made: “This is now bone of my bones, and flesh of my flesh: she shall be called Woman, because she was taken out of Man.” The New Testament also chimes in, stating, “He that loves his wife loves himself.”  Echoing Genesis 1:27 and 2:24, Jesus said, “From the beginning of the creation, God ‘made them male and female.’ ‘For this reason a man shall…be joined to his wife, and the two shall become one flesh.’”

Given the Genesis account, we would expect that men and women are designed in complimentary ways that enable them to raise families and rule over earth better than either one of them could do alone. The differences between men and women are good and are by design. They are equal but not interchangeable. Together, man and woman reflect the image of God. Given this biblical idea, next we’ll discuss some of these differences, going from head to toe.

First, there’s vision. To begin with, women’s pupils are actually 9% larger than men on average.  Ever hear the saying that your mom has “eyes in the back of her head”? Well—it turns out that women have better peripheral vision. Women have better color perception and men require a slightly longer wavelength of a color to experience the same shade as women. Men are also 17 times more likely to be color blind than women.  Men have greater sensitivity for fine detail and for rapidly moving objects.  Scientists have learned that this results from hormonal differences between males and females during fetal development, with the male brain having higher concentrations of androgen receptors in their visual cortex, resulting in 25% more of these neurons than females.

Women have much better high-frequency hearing. Scientists have also determined through brain imaging that women listen by using both sides of their brain, while men just use one. Women have a better sense of smell compared to men, with studies showing that women have 43% more cells and almost 50% more neurons in their olfactory centers than men.

Women also have a better sense of taste than men, with studies showing more neurons in the brain’s taste centers. Dr. Bartoshuk, a professor at the University of Florida Center for Smell and Taste, has found that supertasting abilities are more common in women than in men, with 35% of women making the “supertaster” rank compared to only 15% of men.

Next, on to the skull and brain. There are pronounced differences between male and female skulls in weight, size, capacity, and even shape.  And inside of those skulls, there’s a whole lot of differences going on too…

To begin with, men have 6.5 times more gray matter associated with intellectual functioning compared to women, and women have 9 times more white matter involved in intellectual function compared to men. Also, 84% of the gray matter correlated to intelligence in women is located in the front part of the brain, compared to only 45% in men. Even greater differences exist with white matter, where 86% of the volume responsible for intelligence is in the front part of the brain, compared to 0% in men. The gray matter driving male intellectual performance is distributed throughout more of the brain.

A new scientific study of 118 babies revealed major differences in how male and female brains develop in the womb, even before conditioning from parents and culture come into play.  This study revealed significant differences in 7 of 16 functional connection networks between males and females, and these begin just weeks into the baby’s development.

Another major study used advanced imaging techniques to trace and highlight the fiber pathways connecting the different regions of the brain.  Nine-hundred-and-forty-nine brain scans revealed greater neural connectivity from front to back and within one hemisphere in males. This indicates that the male brain is designed to facilitate greater connectivity between perception and coordinated action. In females, the researchers found that the wiring was generally greater between the left and right hemispheres. This connectivity facilitates better communication between the analytical and intuitive compared to males. The lead scientist on the study noted, “These maps show us a stark difference—and complementarity in the architecture of the human brain that helps provide a potential neural basis as to why men excel at certain tasks, and women at others.”

Researchers also added that these differences may explain why men tend to be better at learning and performing a single task, like cycling or navigating, and why women are better at multitasking.  The same volunteers in the study performed a series of cognitive tests which supported these conclusions; women did well on tasks related to attention, word, and facial memory, whereas men did well on spatial processing and sensory motor speed.

Could it be that these major wiring distinctions are by design? Something that our Creator set into our male and female blueprints to complement each other in life, work, and raising children? We certainly think so.

Another recent study on over 1,000 brains unveiled differences between male and females that were so profound that scientists were able to predict whether the brain belonged to a man or woman with 93% accuracy.  This image shows the areas with most extreme differences in orange and red.  Interestingly, many of these areas relate to self-consciousness, self-awareness, and parts of our brains that are activated when we model other people’s views, or when deciding to act out of empathy and forgiveness.  Each of the 10 brain characteristics shown here can predict whether a brain belongs to a man or a woman with over 86% classification power.

Next, we have the corpus callosum, the largest connective pathway in the brain that consists of a thick band of 200 million nerve fibers serving as a super highway between the left and right hemispheres. This pathway allows communication between both sides of the brain. Studies have revealed women have a 7% larger corpus callosum, even controlling for brain size. This agrees with another major study that revealed the two hemispheres of a woman’s brain talk to each other more than a man’s.

When controlling for overall brain size, men have more grey matter than women, and women have more white matter which is responsible for communication between different areas of the brain. The neurons are also packed more tightly in women’s brains, and these differences are present from birth.

Dr. Diane Halpern, past president of the American Psychological Association concluded these innate differences between male and female brains explain differences in cognitive abilities. In the preface on her book on this topic, she observed: “it seemed clear to me that any between-sex differences in thinking abilities were due to socialization practices, artifacts and mistakes in the research, and bias and prejudice. … After reviewing a pile of journal articles that stood several feet high and numerous books and book chapters that dwarfed the stack of journal articles … I changed my mind.” Why? There was too much data pointing to the biological basis of sex-based cognitive differences to ignore.  Halpern states, “These findings have all been replicated. Women excel in several measures of verbal ability—pretty much all of them, except for verbal analogies. Women’s reading comprehension and writing ability consistently exceed that of men, on average. They out-perform men in tests of fine-motor coordination and perceptual speed. They’re more adept at retrieving information from long-term memory. Men, on average, can more easily juggle items in working memory. They have superior visuospatial skills: They’re better at visualizing what happens when a complicated two- or three-dimensional shape is rotated in space, at correctly determining angles from the horizontal, at tracking moving objects and at aiming projectiles.” Halpern adds that many of these cognitive differences appear very early in life: “You see sex differences in spatial-visualization ability in 2- and 3-month-old infants.” “Infant girls respond more readily to faces and begin talking earlier. Boys react earlier in infancy to experimentally induced perceptual discrepancies in their visual environment. In adulthood, women remain more oriented to faces, men to things.”

Do these design differences limit men and women to filling only certain career roles? Certainly not. Men and women capably fill many different kinds of occupational roles with great success! But some of the design differences between men and women have contributed to men and women stacking up unevenly in certain jobs. Consider that women make up over 92% of nurses, 98% of preschool and kindergarten teachers, and 98% of dental hygienists in the U.S. Men make up over 93% of the welders, 99% of the brick masons, and 98% of the small engine mechanics. This does not mean that women can’t be top notch lawn mower mechanics, or men can’t be very effective dental hygienists. But millions of men and women fill these roles and they do in fact seek out and excel at different careers, and biological drivers play a big part. Has culture and upbringing also contributed to these differences? Absolutely. Sadly, discrimination has too.

Moving on, consider that our vocal cords are different too  and most women don’t have a pronounced Adam’s apple—that’s something that happens to boys as testosterone is increased during puberty. Testosterone causes his larynges to expand and meet the thyroid cartilage at an angle, lowering and deepening the male voice. These vocal differences seem fitting to the roles suiting males and females.  A child draws comfort from the soft voice of his mother, and assurance from a loving father. Together, men and women join to produce some of the most heavenly sounds in harmony… (see video above).

Women’s faces even have twice the number of nerve cells as men, making them more sensitive to touch sensations and pain.  Men and women also by design store fat in different places, contributing to the body differences that are so obvious in men and women.

Skin also differs between men and women. Androgens, including testosterone, yield a denser network of collagen fibers than that found in female skin. The result is skin that’s over 20% thicker in men than in women.  Studies have shown that wounds don’t heal as quickly in men, in part due to the testosterone.

Men and women also differ when it comes to diseases. Women are twice as likely to experience clinical depression. Men are twice as likely to become alcoholic or drug-dependent, and 40 percent more likely to develop schizophrenia. Boys’ dyslexia rate is 10 times that of girls, and they’re at least three times more likely to be autistic.

Pharmacists even prescribe certain medicines to men and women differently. For example, men and women metabolize the sleep medicine Ambien differently, so the dosage for women was recently reduced by the FDA. The reason was due to “Sex differences found in pain receptors, liver enzymes, and even the wiring of the brain.”

All these differences between men and women are real, and they’re all present at birth before parenting or culture come into play.  While we’ve focused on most of the unseen differences between men and women, there are also more obvious differences in height, size, and shape, and other areas as well.

Clinical psychologist Dr. Jordan Peterson, professor at the University of Toronto, briefly sums up the key differences between men and women this way… (see video above).

It’s quite obvious that these biological differences between men and women will also drive parental roles and styles in different ways. For example, some studies have confirmed that even though “men and women show no significant difference in how they attempt to comfort their toddlers, children respond differently to each parent.” Specifically, “children of mothers who engaged in more physical comfort and reassurance reported higher levels of pain intensity,” confirming that children reported higher pain tolerance and less pain overall when fathers were doing the comforting. This simply means that children are more comfortable exaggerating their pain to mothers, but when fathers are around, children act tough.”

Next let’s take a look at sex. From a biblical standpoint, Jesus sums up the reason for sex in a couple of verses: “He who made them at the beginning ‘made them male and female,’ and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’ So then, they are no longer two but one flesh. Therefore what God has joined together, let not man separate.” Here Jesus describes the biblical covenant of marriage and quotes Genesis in two places. This passage clearly lays out a man and a woman joining their bodies to become one, and it is only through this bonding that children are produced. This is taught throughout the pages of Scripture and naturally progresses into biblical fatherhood and motherhood, two other topics on which the Bible has much to say.

Leading up to this marital connection is a host of processes designed to lead to marriage, sex, and raising children. We have the hormones driving men and women together, the process of falling in love, and even feelings of jealousy that can motivate exclusivity between couples.

When couples join in this process of oneness, neurochemical processes occur which generate the glue of bonding between couples. “Women are more sensitive to the effect of oxytocin, a hormone that is also found to be a bonding hormone released during childbirth and nursing. As oxytocin is released during sex, it “acts as emotional super glue between partners.” Men are more affected by vasopressin, which similarly “helps a man bond to his partner and instills a protective instinct toward his partner and children.” In the biblical framework, these hormonal reactions help bond couples into making long-term committed relationships.

However, when activated during casual sexual relationships, they can cause much trouble. According to neuropsychologist Dr. Jennings: “When you have premarital sex, your reward circuitry is bonded to them now, and it will be much deeper and hurtful. Oftentimes, in breakups of people who’ve been sexually active, they can’t tolerate the sense of emptiness, so they rush into another relationship. The neuro circuits did not have time to reset, and so they’re impaired in their ability to bond with the next person, and they may become sexually active with them. This is just a repetitive cycle, and there are real impairments in bonding going on. God wired and designed our brains for a specific purpose: to bond ourselves with the person we marry.”

Sex also happens to be a great example of irreducible complexity in God’s design. Men and women fit perfectly together—and are quite motivated to do so. Indeed, everything about sex, from the drive that leads to it, the chemicals and hormones that join soul and flesh in oneness, to the outcome that comes from it—childbearing—are all an undeniable creation of God. Evolution has tried for 150 years and admits they can’t explain how the division of sexes came to be. Both sexes must be present at the same time to have offspring. Genesis provides the better explanation, with males and females right at the outset of Creation.

Sex also has significant theological implications. Genesis explains why sex is placed within the structure of marriage and this covenant bond between a man and a woman reflects the covenant bond between Christ and His bride, the church. This topic is very important to God. The Bible begins with a marriage and ends with a marriage.

This background also demonstrates why sex outside of a biblical marriage is strongly warned against throughout the Bible. Sex is a gift from God that should be cherished. Like a fire kept in a fireplace can heat a home, but outside a fireplace can burn down the house, sex should be kept within the confines that God intended. In fact, researchers have found that those who wait to have sex until marriage, compared to those who don’t, report significantly higher relationship satisfaction (20%), better communication patterns (12%), less consideration of divorce (22%), and better sexual quality (15%).

Next let’s look at the result of sex between a man and woman: conception. Check out this video showing the release of zinc molecules that happens the moment an egg is fertilized. Special fluorescent molecules allow us to see this amazing moment. Whether baby will be a boy or a girl is instantly determined by the man’s specific sperm cell that fertilizes the woman’s egg. It takes a man and woman to make this process happen. Every other biological function requires only a single body. Digestion. Respiration. These and other functions that are key to life can be done by a single person. The single exception is procreation. This demonstrates that men and women are incomplete and designed for each other. Unless they join as one flesh, procreation does not occur.

The amazing markers of God’s design don’t stop after the baby arrives. Did you know that breastfed babies usually grow up to have higher IQs? The perfect mix of nutrients are contained in mother’s milk—far better than manmade formulas. They’ve even recently learned that during breastfeeding the baby’s saliva combines with breastmilk to create hydrogen peroxide to regulate the growth of bacteria, at high enough levels to kill opportunistic pathogens for up to 24 hours, but allow others to grow.  Another amazing discovery is that the composition of a mother’s breastmilk can even change based on the sex of the baby!  The milk that mothers produce while nursing boys has higher fat content than girls. Now just how does a woman’s body know how to do that!?

In conclusion, professor Budziszewski sums it up well by saying, “Even more remarkable is that the complementarity of wife and husband does not end with biology. In every dimension, physical, emotional, and intellectual, they fit like hand in glove; they match. The woman is better designed to nurture the child, to establish the family on the hearth, and to model how these things are done. The man is better designed to protect the mother and child, to establish the family in the world, and to model how these things are done. Even the virtues, though needed by both sexes, have male and female inflections. When escape is possible it is not an act of courage but rashness for an endangered woman to stay and fight, because she carries in herself the possibility of the next generation. But it is not an act of prudence but cowardice for the man to decline to defend her, because his life is only one. We may add that it is not an act of justice but of foolish injustice to pretend that the sexes are the same. Justice is exercised in respectfully providing for the due needs of each.”

Men and women have Genesis one blueprints but we also live in a Genesis three world, marred by the fall. The expressions of humanity that go against God’s design, marital covenant, and laws are far and wide. Going against them wrecks relationships, families, and futures. Living within them brings life, safety, nurture, and legacy. What God has laid out is clear, but He leaves the choices up to us. Every one of us has sinned, including sexually. We’ve all gone against God’s best in one way or the other. But through Christ there is hope. There is forgiveness. There can be a fresh start. Restoration and healing await those who repent.