What does the Bible say about true preachers?

According to the sermon, true God-sent preachers have one primary focus: Jesus Christ. Their entire ministry revolves around declaring the gospel of Jesus Christ and Him crucified. As seen with John the Baptist, who was specifically sent by God to bear witness of the light, true preachers will not seek glory for themselves but will point others to Christ, admitting their own unworthiness in the face of His eternal worth. John said, 'I am not the Christ,' demonstrating a clear understanding of his role as a messenger rather than a source of authority.