We learn in psalm 127 that God is the one who gives success and growth and defense to his people. It is not the work of man, it is the gift of God. 

In the church, God is the one who grants growth to his people. This keeps us from boasting. 

Likewise, God grants us rest. We find here then that it is in rest that God grants even the fruit of the womb. Children are then seen to be a blessing from God and that man will be blessed who has many. 

Children are then used to shape the future and create culture. 

In the end, it is through the Blessed Man, Jesus Christ, and his people who will shape eternity.