I’ve been talking about this for a long time, and will continue to. The common misunderstanding about God’s command to “be fruitful and multiply” is that reproduction is a private choice, affecting only the private lives of each family (therefore, “stay out of my business”).
We fail to understand that many principles of Scripture are not individualized; they are given to “a people” and the obedience or disobedience affects “a people”. God’s ways are not always meant to be interpreted as a tool to improve or hinder our personal lives, though He is deeply concerned with us on a personal level. But “His ways are higher than our ways” and we would do well to just trust that.
What I’m trying to say is, often God is wanting to do something much bigger than the scope of our own lives with our obedience to Him. And even in His sovereignty, He allows us to reap blessings or curses based on that obedience.
Pay close attention to this verse and keep it close while you watch the following, short video about our changing demographics due to low fertility rates among Christians (it’s a little different spin than “Demographic Winter”):
“If you fully obey the Lord your God and carefully follow all his commands I give you today, the Lord your God will set you high above all the nations on earth. All these blessings will come upon you and accompany you if you obey the Lord your God…
However, if you do not obey the Lord your God and do not carefully follow all his commands and decrees I am giving you today, all these curses will come upon you and overtake you…
The alien who lives among you will rise above you higher and higher, but you will sink lower and lower.”
From Deuteronomy 28:43