In the sermon titled "Exiles: A Holy Nation (Week 2)," the speaker delves into the role of believers as a "royal priesthood" as described in 1 Peter 2. He contrasts this role against the backdrop of persecution endured by early Christians under Emperor Nero, emphasizing the calling of modern believers to represent God's Kingdom through service and sacrifice. The message highlights that being part of God's Kingdom is not about earthly opulence but about being dedicated servants who embody and proclaim Kingdom values. The speaker challenges believers to actively participate in their priestly duties, thereby contributing to the spiritual well-being of the world.