The Bible states that 2 people can populate a planet to 7 billion. That’s impossible
But the claim that it is impossible to get seven billion descendants from two people is 100% wrong. The Bible reveals that God, who is all-powerful, created two people initially (Genesis 1)—a man and woman (Genesis 1:26–27) called Adam and Eve (e.g., Genesis 2:19, 3:20; 1 Timothy 2:13). Adam was the first man (1 Corinthians 15:45), and Eve was the mother of all the living (Genesis 3:20).
Allow me to state the obvious to make some points: parents produce children. Those children grow up and produce children, and the process continues. Scientifically, we can test this: humans have more humans. Since mankind was commanded to be fruitful and multiply, childbearing and population growth is appropriate (Genesis 1:28).
Adam and Eve had many sons and daughters over the course of many years (Genesis 5:4), so, yes, originally brothers and sisters had to marry. That was admissible originally of necessity (and not a problem for genetic diseases that wouldn’t have existed yet so soon after the degenerate effects from sin and the curse), but God set up most familiar incest laws at the time of Moses (e.g., Leviticus 18), which was about 2,500 years after Adam and Eve. So from the Christian position, it is no longer appropriate to marry close relatives. Some still defy God’s command against this (see: “A Mother in Oklahoma Married Her Son and Then Her Daughter, Who Just Pleaded Guilty to Incest, Officials Say” and “‘I’ve Married My Sister —Now We’re Having Our Second Baby’: Siblings Who Defied Law Plan to Start New Life Abroad.”).
Actually, we would have gotten to seven billion sooner if it hadn’t been for sin and the flood of judgment on that sin.
Actually, we would have gotten to seven billion sooner if it hadn’t been for sin and the flood of judgment on that sin (Genesis 6–9). That event reset the population to eight people, where six of them (Shem, Ham, and Japheth’s families) were responsible for populating the earth (e.g., Genesis 6:10, 7:7, 8:16, 10:32). And population stats reveal that since the flood (about 4,350 years ago), we should be at about 6–7 billion people right now even at a conservative rate of doubling only every 150 years. Do the math.
Consider the secular view that seven billion people on the earth came from an almost infinitely dense and hot matter that exploded and came from nothing, yet there is no criticism there?1 Let’s evaluate this. Do people come from people or do people come from inanimate material? We observe people coming from people, but people don’t come from rocks. One of these views is logical and clearly possible—one isn’t.
In a few thousand years, we expect only seven billion humans. But calculating how many humans there should be in tens of thousands of years doesn’t add up—or rather adds up quite a bit too much! I want to encourage you to trust God’s Word as the supreme authority for a starting point on the origin of people.