Our Lord did not provide His body with multiple missions. He did not tell some to make disciples, but others to do other things. Christ is not a God of confusion; therefore, He has made things fairly simple for us to comprehend. Near the end of each of the four gospel accounts we read His charge to His followers. Although the wording is different in each passage, it should be noted that in each one Jesus is clearly sending them all out into the world.
The four gospel passages:
And Jesus came and said to them, "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)
Afterward he appeared to the eleven themselves as they were reclining at table, and he rebuked them for their unbelief and hardness of heart, because they had not believed those who saw him after he had risen. And he said to them, "Go into all the world and proclaim the gospel to the whole creation." (Mark 16:14-15)
Then he said to them, "These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled." Then he opened their minds to understand the Scriptures, and said to them, "Thus it is written, that the Christ should suffer and on the third day rise from the dead, and that repentance and forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem." (Luke 24:44-47)
Jesus said to them again, "Peace be with you. As the Father has sent me, even so I am sending you." (John 20:21)
Immediately following the gospels we read this at the beginning of Acts:
"But you will receive power when the Holy Spirit has come upon you, and you will be my witnesses in Jerusalem and in all Judea and Samaria, and to the end of the earth." (Acts 1:8)
Jesus is clear. He has given us one mission to take the good news of His salvation to the ends of the earth and make disciples while doing so. Since this mission is well-defined, there should be no confusion on the part of His church. This being the case, let's rally together around this disciple-making mission. Only when we work together will we be able to accomplish the unfinished task.