Pastor Nick's sermon on Nehemiah emphasizes the importance of rebuilding and protecting our faith and community in the face of opposition. He draws parallels between the challenges faced by Nehemiah and the modern-day struggles that Christians encounter, urging the congregation to stand firm in their beliefs and to support one another through prayer and action. The pastor highlights the need for vigilance against spiritual and cultural attacks while encouraging believers to work diligently for their families and their church. Ultimately, he reassures everyone that God is mighty and will empower His people to overcome obstacles and fulfill their calling.