T. Austin-Sparks emphasizes the distinction between the position of believers in Christ and their actual spiritual condition, as illustrated in his examination of the Corinthian church. He highlights that while some members were failing, others were overcoming, and the letters to the churches serve as an appeal to align with God's full thought. Using Levi as an example, he illustrates the necessity of spiritual separation from natural influences to truly represent God's will. The sermon calls for a commitment to God's full thought, which may require personal sacrifice and a rejection of worldly wisdom. Ultimately, those who embrace this path become instruments of divine revelation and ministry.