It came and went quietly, but the human race just passed a significant milestone: On Feb. 25, at 7:16 p.m. Eastern Standard Time, the world’s population reached 6.5 billion, according to the U.S. Census Bureau.

It happened less than seven years after the number of people worldwide reached 6 billion. That total, in turn, was reached only 12 years after the 5-billion mark was surpassed. The new count of 6.5 billion is more than twice the size of the population in 1960—and four times the number of humans alive at the beginning of the 20th century.

Global population is not speeding toward the huge, unsustainable masses some demographic doomsayers have long predicted. But it continues to grow. The 7-billion mark will be reached in 2012, according to forecasters. More than 9 billion people will walk the earth by 2050, they estimate, before the global total begins to level off.

A few trends and specifics:

On average, 4.4 babies are born each second.

Most population growth continues in the nations of the global South and East. “Virtually all of world population growth now takes place in developing countries,” reports Carl Haub, senior demographer at the Population Reference Bureau. “Europe now has more deaths than births each year…. The few developed countries that still have more births than deaths, such as the United States, owe much of their growth to immigration from developing countries.”

The poorest countries continue to have the highest birthrates. Women average five or more children in countries where per capita annual income is $1,000. In contrast, mothers bear an average of two or fewer children in nations where per capita income tops $12,000.

These numbers have many social and political implications. In the spiritual realm, however, the most urgent message for Great Commission-minded Christians is this: Our evangelization task is unfinished. Mission researchers tell us that, at most, one in every 10 people on earth is a born-again follower of Christ.

The regions of greatest population growth—and, often, greatest physical poverty—also tend to be the regions with the greatest concentrations of spiritual lostness. Case study: West Africa. Malaria, AIDS and other diseases are widespread there. Life expectancy is under 50 years. Malnutrition is high; literacy is low. Half of West Africans live on less than a dollar a day.

More than 350 of West Africa’s 1,612 people groups have no access to the gospel. Half of the region’s entire population of 287 million is unreached (less than 2 percent evangelical). The Wolof people of Senegal and Gambia, for example, number nearly 4.7 million—with fewer than 100 evangelical believers. The 30.3 million Hausa people, the region’s largest unreached group, are less than 1 percent Christian. International Mission Board missionaries currently work among only 52 West African people groups.

South Asia is home to 1.45 billion people. That includes the more than 1 billion people of India, a nation that will overtake China as the world’s most populous if growth trends continue. In all of South Asia, evangelical Christian believers comprise less than 2 percent of the population.  

In recent years Southern Baptists and other Great Commission groups have made enormous progress in engaging (assigning missionaries, plans and resources to reach) all the world’s unreached megapeoples—those with more than 1 million members. Now they are focusing on engaging the hundreds of untouched groups with populations between 100,000 and 1 million. 

But “engaged” doesn’t mean “evangelized,” stresses International Mission Board President Jerry Rankin. “Our goal is for every person to hear the gospel. How can they respond unless they have heard?”

The church has many God-given ministries, but giving the lost the opportunity to hear the Good News of Jesus remains our top priority. According to Jesus’ Great Commission in Matthew 28:19-20, the way to accomplish it is very specific: “Go therefore and make disciples of all the nations (peoples), baptizing them in the name of the Father, and the Son and the Holy Spirit; teaching them to observe all that I commanded you....”

“We have had a tendency to dilute the Great Commission to mean whatever we do in missions, evangelism, and ministry,” Rankin observes. “(But) in the Greek language, ‘make disciples’ is one word; it is an imperative verb and the object is ‘all peoples.’

“God’s heart and mission is that all peoples know Him. Our mission can be no less.”

In a lost and chaotic world of 6.5 billion, we need the clarity of God’s mission more than ever.