"And God blessed them, and God said unto them, Be fruitful, and multiply, and replenish the earth, and subdue it: and have dominion over the fish of the sea, and over the fowl of the air, and over every living thing that moveth upon the earth" (Genesis 1:28).
This "dominion mandate," as it has been called, was the very first command of God to the first man and woman. It applies to the whole earth; all its processes, and all its creatures. To subdue the earth and control it implies the development of science and technology, commerce and education--indeed every honorable human vocation. As God's first "great commission," it applies to all people and has never been withdrawn. God even expanded it to Noah after the Flood (Genesis 9:1-7), twice repeating the command to "be fruitful, and multiply."
In order to really subdue and exercise dominion over the earth, a large population would be necessary. Despite all the concern in modern times about population growth, God's command has never yet been fully accomplished. Vast areas of the earth are still barren and undeveloped.
Furthermore, the great majority of humans are oblivious to the dominion mandate and live their lives utterly without concern for the will and purpose of their Creator. Therefore, He has given another Great Commission to those who do love God, trusting Him as both Creator and Savior, and this also involves the whole world. Jesus said to His disciples: "I have chosen you, and ordained you, that ye should go and bring forth fruit, and that your fruit should remain" (John 15:16). That is, we who are His disciples are also to be fruitful and multiply spiritually, as well as physically. Then, in the age to come, the first great mandate will also finally be fulfilled, "for the earth shall be full of the knowledge of the LORD, as the waters cover the sea" (Isaiah 11:9). HMM