Matthew 28:19-20
Therefore go and make disciples in all the nations, baptizing them into the name of the Father and of the Son and of the Holy Spirit,
20 and then teach these new disciples to obey all the commands I have given you; and be sure of this--that I am with you always, even to the end of the world."
Our opening scripture is God's instruction to everyone who has received Christ, you are to take message of salvation to the world. You are to reach those in your world and teach them how to live and walk in righteousness.
The word "nation" doesn't mean countries, it is derived from the Greek word "ethnos", which refer to different groups of people, sharing a common interest. It is our obligation to take the gospel to every man's world; to the various groups to which they belong. You are God's voice to them, you are a missionary, an oracle of God, commissioned to help the uncovered in your world to receive salvation and teach them the word.
God has made you a man or woman of influence in your world, use your influence for Him, make impact with the gospel, let more people in your world come to the knowledge of Christ through you.