In "The Holy Ghost—The Great Teacher," Charles Spurgeon emphasizes the pivotal role of the Holy Spirit in illuminating and imparting divine truths to believers. Spurgeon describes the Holy Spirit as the ultimate instructor who guides Christians into a deeper understanding of Scripture and God's will. The sermon outlines how the Holy Spirit teaches through conviction, comfort, and enlightenment, ensuring that believers grasp the spiritual significance of their faith. Spurgeon underscores the necessity of relying on the Holy Spirit for true wisdom and discernment, positioning the Spirit as an indispensable guide in the believer's spiritual journey and growth in godliness.