John 17.13-19 “I am coming to you now, but I say these things while I am still in the world, so that they may have the full measure of my joy within them. I have given them your Word and the world has hated them, for they are not of the world any more than I am of the world. My prayer is not that you take them out of the world but that you protect them from the evil one. They are not of the world, even as I am not of it. Sanctify them bythe truth; your Word is truth. As you sent me into the world, I have sent them into the world. For them I sanctify myself, that they too may be truly sanctified.
Before Jesus leaves His disciples to return to His Father, He summarizes the Christian life for them. First, He reminds them they are to remain in the world but not be of the world. They are a new and different people now, so they no longer live for the treasures and pleasures this world entices men to give their lives in pursuit. The disciple is to reflect the nature and objective of the Teacher. His character and His mission are to be their character and their mission. The food of God in Jesus is the Word of God. This is His second point. The Word makes the disciple like Him. Daily intake and commitment to obedience to the Word of God make the disciple of God like the Son of God. We cannot be like Jesus without being like Jesus in His commitment to knowing and obeying the Word of God. Finally, Jesus reminds us of His mission for us. We are different from the world because we are in the world calling people out of this world and into life in the kingdom of God. The Great Commission is the mission of every Christian, and we are to be fully engaged in seeking and saving the lost, just as the Savior. Jesus has saved us to send us to save others through the proclamation of the gospel while we live the gospel proving its truth.