In the beginning, God created every living thing in the air, land and sea. He blessed them and commanded them to bring forth fruits and multiply and fill the face of the earth. I don't want to go too dip into how God created everything but you can find it in Genesis 1:20-28. from then on till now, every living thing has justified that mandate of fruitfulness. The plants, animals and birds have all multiplied that they are beyond numbering today. God put in to man the needed faculties to produce and they are producing.
I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful. - John 15:1-2 NIV.
Just as nature has obeyed God and multiplied, God is commanding the believers to equally bring forth fruits which means souls in to the kingdom of God. Whereas Adam and Eve was mandated to fill the face of the earth with people, Jesus is asking us to go bring souls to fill the kingdom of heaven that is coming. There is a real kingdom somewhere in the heaven that shall soon be revealed where we shall all go. Jesus is preparing the kingdom for us. We must labor to bring people in to the kingdom.
Do not let your hearts be troubled. You believe in God; believe also in me. My Father’s house has many rooms; if that were not so, would I have told you that I am going there to prepare a place for you? And if I go and prepare a place for you, I will come back and take you to be with me that you also may be where I am. - John 14:1-3 NIV.
What, after all, is Apollos? And what is Paul? Only servants, through whom you came to believe as the Lord has assigned to each his task. I planted the seed, Apollos watered it, but God has been making it grow. So neither the one who plants nor the one who waters is anything, but only God, who makes things grow. The one who plants and the one who waters have one purpose, and they will each be rewarded according to their own labor. For we are co-workers in God’s service; you are God’s field, God’s building. - 1 Corinthians 3:5-9 NIV.
The way to fill the kingdom of heaven with people is by sowing the seed of the word of God. As we go one on one, two by two, group evangelism, we scatter the seed of the word of God. When God waters it, it will bring forth fruits for everlasting life.
You did not choose me, but I chose you and appointed you so that you might go and bear fruit fruit that will last and so that whatever you ask in my name the Father will give you. - John 15:16 NIV.
Our prosperity is tied to our fruitfulness. The Bible makes us understand that if we bring forth fruit, our God will be glorified and whatever we ask in the name of Jesus, the father will do it.