Duane Troyer preaches on the story of Nehemiah, highlighting his unwavering faith, dedication, and leadership in rebuilding the walls of Jerusalem amidst adversity and opposition. Nehemiah's ability to discern between true concern and deceit, his focus on the work of God despite false rumors and threats, and his commitment to prayer and unity among the people serve as powerful lessons for believers today. The sermon emphasizes the importance of having a vision for God's kingdom, being watchful, discerning, and dedicated to the work set before us, even in the face of challenges and distractions.