Why has God left me here on earth?

Recently I was listening John MacArthur preach and he said something that has stuck in my mind. He said basically that the reason we, as Christians, are still here on earth and not in heaven is primarily to evangelize those who are not Christians. God does not leave us here primarily to worship Him, because we will do it much better in heaven. He does not leave us here to be holy, because we certainly will be much more holy in heaven with our glorified bodies. He leaves us here on earth, because there's still the need to evangelize. We will not evangelize in heaven because we will not need to. Most of this was said by MacArthur. What do you think? Is this primarily the reason that we are still here on earth and therefore, our life's purpose? I think it is.

I have started putting together a purpose statement for my life to keep me focused. Here's what I have so far: I am still alive here on this earth to magnify God and His Son so as to gather more worshipers/God-glorifiers (I'm inventing a new word here). Magnifying Him is not the end but a means to the end. Just as a telescope shows small-looking things as they really are--BIG, so we are to show Christ as He really is (we do our best, at least). As we magnify Christ, some see Him for who He is and some do not. (II Cor. 4:3-4) I believe God has determined to gather worshipers through a certain means which is: God's Word of the cross + Holy Spirit + worshipers like you and me= more worshipers of God. This is ultimately why I am still alive. One other thing that I have thought of is the importance of first being a worshiper of God myself and then also helping other Christians(such as my wife, kids, friends, brothers and sisters at church) to be true worshipers of God, so we can all gather more new worshipers of God.

David, and others who read this, Please tell me what you think. I do not want to waste my life. I want to make each day count for the purpose for which God has granted that day to me. Please pray for me now as well to live this way for His glory.

JT