Jesus defined the mission of every Christian church when He told His Disciples, "All authority in heaven and on earth has been given to me. Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age" (Matthew 28:18-20). We are to make disciples of all nations. No one is excluded. In order to make disciples, Jesus instructs us to baptize in the name of our Triune God and teach what He has commanded, which has been written down and collected for us in the Bible.
The Gospel of John also says this about Jesus: "In him was life, and the life was the light of men. The light shines in the darkness, and the darkness has not overcome it" (John 1:4-5). Jesus is the Light of the world. He brings us life. There is no life outside of Jesus.
Therefore, our mission is to reflect the light of Jesus Christ by sharing the Good News of salvation with all people and by nourishing the faithful through His Word and Sacraments.