Here’s a scary thought for Halloween: today marks the rollover to a world population of 7,000,000,000 people.  Some say: No problem; God will provide.
Not me.  This freaks me out.
I recently came across the television show 19 Kids and Counting (yeah, I know—where have I been?).  It’s the story of Jim Bob and Michelle Duggar and their 19 children.  No, they don’t adopt needy children, they make them the old-fashioned way.
Their web site is full of Christian talk, links to Creationist sites, and ads for Christian products.  Here they talk about birth control.

We prayed and studied the Bible and found a host of references that told us God considered children a gift, a blessing, and a reward. Yet we had considered having another child an inconvenience [by the wife taking birth control pills] during that busy time in our lives, and we had taken steps to prevent it from happening.
We weren’t sure if Michelle could have any more children after the miscarriage, but we were sure we were going to stop using the pill. In fact we agreed we would stop using any form of birth control and let God decide how many children we would have.

This is the thinking of the Quiverfull movement, whose name comes from Psalm 127: “Like arrows in the hand of a warrior, so are the children of one’s youth.  How blessed is the man whose quiver is full of them.”  From Quiverfull.com:

We exalt Jesus Christ as Lord, and acknowledge His headship in all areas of our lives, including fertility.  We exist to serve those believers who trust the Lord for family size….

What kind of childish logic is this?  Maybe during the Bronze Age, people could say, “We’ll let God decide how many children we’ll have,” but today, we know very well where children come from and how to avoid them.
If you drink poison, you’re not letting God decide whether you live or not; you’re deciding.  If you wave a gun in a bank, you’re not letting God decide whether you get arrested or not; you’re deciding.  And if you have frequent unprotected sex, you’re not letting God decide how many children you have; you’re deciding to have as many as biologically possible.
Quiverfull aficionados reject all forms of birth control.  But if vaccines and antibiotics aren’t messing with God’s plan, why would contraception—not killing an embryo but simply preventing it from happening—be a problem?
Back to the Duggar family, someone might respond that they’re paying their way.  They’re not asking for handouts, so what’s the problem?
The problem is that the planet has a finite carrying capacity.  There’s only so much oil, fresh water regenerates only so fast, and so on.  To make it worse, Americans live a rich life compared to most other people.  For example, the resources that support these 19 kids, assuming they consume at the rate of average Americans, could support 600 average Kenyans.
“God will provide” might satisfy a child, but adults should know better.
In a discouraging article that concludes that religious believers will simply outbreed their competitors, author Tom Rees says:

In Israel and Palestine, both orthodox Jews and religious Muslims have astonishingly high birth rates, at least in part as a consequence of waging war “by other means.”  Throughout the Islamic world, those who have the most extreme beliefs are also the most likely to endorse the desirability of large families.

That other guy thinks he’ll win by having more children?  We’ll have even more than that—we’ll fight fire with fire!
We find similar thinking in the U.S.  Again, from Quiverfull.com:

Quiverfull mothers think of their children as no mere movement but as an army they’re building for God.

But is that the way to play the game—we just descend to the other guy’s level?
Is there no role for reason here?  You don’t fight fire with fire, you fight it with water!
Related links:

• No Longer Quivering is a site that provides education and support to those getting out of the Quiverfull movement.
• Bryan Walsh, “The World at 7 Billion: Why the Real Victim of Overpopulation Will Be the Environment,” Time, 10/26/11.
• Elizabeth Kolbert, “Billions and Billions,” The New Yorker, 10/24/11.
• Tom Rees, “Shall the fundamentalists inherit the earth?” Epiphenom blog, 5/4/10.
• “Overpopulation,” Wikipedia.