G. Campbell Morgan emphasizes the believer's responsibility to respond to the progressive revelation of Christ through the Holy Spirit. As the Spirit unveils new aspects of Christ, it demands obedience from us, urging us to walk in the light we receive. Morgan illustrates that failing to respond leads to spiritual decline, while obedience transforms us into the likeness of Christ. He encourages believers to actively cooperate with the Spirit, recognizing that our duty is to answer the call of truth and allow the Spirit to work dynamically within us. Ultimately, our response to the light we receive shapes our witness to the world.