Pastor Nathan Francis' sermon "Expository Preaching" delves into Nehemiah 8, where Ezra reads the book of the law to a united Israel, leading to transformation and worship. Divided into explaining, transforming, and emphasizing the power of the Bible, the sermon praises expository preaching for focusing on biblical texts and their impact on listeners. It highlights the Bible's ability to unify, transform, and convict, stressing the necessity of understanding and responding to God's Word in worship and personal growth.