Matthew 28:18-20 (NIV)
18 Then Jesus came to them and said, “All authority in heaven and on earth has been given to me. 19 Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 and teaching them to obey everything I have commanded you. And surely I am with you always, to the very end of the age.”
Acts 1:8 (NIV)
8 But you will receive power when the Holy Spirit comes on you; and you will be my witnesses in Jerusalem, and in all Judea and Samaria, and to the ends of the earth.”
2 Corinthians 5:16-20 (NIV)
16 So from now on we regard no one from a worldly point of view. Though we once regarded Christ in this way, we do so no longer. 17 Therefore, if anyone is in Christ, the new creation has come: The old has gone, the new is here! 18 All this is from God, who reconciled us to himself through Christ and gave us the ministry of reconciliation: 19 that God was reconciling the world to himself in Christ, not counting people’s sins against them. And he has committed to us the message of reconciliation. 20 We are therefore Christ’s ambassadors, as though God were making his appeal through us. We implore you on Christ’s behalf: Be reconciled to God.