God expects those who bear the name of Christ to represent Him. Their thoughts are to be pure, their words noble and uplifting. The religion of Christ is to be interwoven with all that they do and say. They are to be a sanctified, purified, holy people, communicating light to all with whom they come in contact. It is His purpose that by exemplifying the truth in their lives they shall be a praise in the earth. The grace of Christ is sufficient to bring this about. But let God's people remember that only as they believe and work out the principles of the gospel can they fulfill His purpose. Only as they yield their God-given capabilities to His service will they enjoy the fullness and the power of the promise whereon the church has been called to stand. CT 322.2
Before Christ went to His final conflict with the powers of darkness, He lifted up His eyes to heaven and prayed for His disciples. He said, “I pray not that Thou shouldest take them out of the world, but that Thou shouldest keep them from the evil. They are not of the world, even as I am not of the world. Sanctify them through Thy truth: Thy word is truth.” John 17:15-17. CT 322.3
The followers of Christ are to be separate from the world in principles and interests, but they are not to isolate themselves from the world. The Saviour mingled constantly with men, not to encourage them in anything that was not in accordance with God's will, but to uplift and ennoble them. “I sanctify Myself,” He declared, “that they also might be sanctified.” John 17:19. So the Christian is to abide among men, that the savor of divine love may be as salt to preserve the world from corruption. CT 323.1