John Wesley preaches on the integrity of preaching the Word of God, emphasizing the importance of sincerity and the dangers of corrupting Scripture through human mixtures and false interpretations. He argues that true preachers must convey the genuine message of God without alteration, and that their actions should reflect their words to gain the trust of their audience. Wesley warns against those who dilute the gospel for personal gain or to please others, stressing that the true purpose of preaching is the spiritual benefit of the listeners. He concludes that preachers must boldly proclaim the entirety of Scripture, regardless of its reception, as they are accountable to God for their message.