John Owen emphasizes the mediatory office of Christ in heaven, illustrating that Christ's role is not merely one of glory but also of active ministry on behalf of the church. He serves as King, Priest, and Prophet, ensuring the church's safety and salvation through His continual intercession and representation before God. Owen highlights that without Christ's mediatory work, believers would lack the assurance and strength needed for their faith and obedience. He also discusses the communion between the church triumphant in heaven and the church militant on earth, underscoring the importance of Christ's ongoing ministry in maintaining this connection. Ultimately, Owen calls believers to recognize and appreciate the profound implications of Christ's mediatory role for their spiritual lives.