Genesis 9:7 And you, be ye fruitful, and multiply; bring forth abundantly in the earth, and multiply therein.
I think that most people do not have a problem understanding that it was possible both for Adam and Eve and also for Noah and his family to reproduce and fill the earth once again.
All they had to do was to reproduce naturally. They would reproduce reproducers. They would have children that would have children that would have children. If that happened it would soon fill the earth.
Even ignoring the fact that before Adam many had lived long lives it is easy to see how that a family that only had 4 children that would average having 4 more children would soon fill the earth.
The first generation would have 2 people that produced 4 more for a total of 6. Those 4 would get spouses and now there are 10. Those 4 children each produce what averages out to 16 children then 64 children. It doesn’t take long for the multiplication to fill the earth.
When we talk of world evangelism most people seem to get bent out of shape. They see it as an impossible task. An unbelievable command that Jesus would expect of His church.
Yet, we have the Holy Spirit, the Word of God, and life to be lived for Him. If each of us took 2 Timothy 2:2 to heart:
And the things that thou hast heard of me among many witnesses, the same commit thou to faithful men, who shall be able to teach others also.
and each began to find and train men who were able to train others we could see this world evangelized. There is no doubt that many will reject Christ. There is no doubt that many will not reproduce but if each of us in our life time could only find, win, and disciple a small number like 4 or 5 the job could be done.
What would happen if each one of us trained 5 reproducers over a lifetime of 50 productive years. Then each of our men trained 5 more. In just 5 generations one man alone would have seen over 6,800 reproduced.
Many of us can influence more than 5 to get the process rolling. This will involve life on life discipleship. It will involve investing your life in others so much that you often lose your own.
It will mean loving them like children. But the job can be done. We should be able to get our heads around training 5 men over a period of 50 years who can train another 5 over 50 years.
Actually this is a very low estimate of what each of us could see done if we so chose!