Paris Reidhead emphasizes that the primary purpose of Christ's coming was to die for humanity's sins and to offer salvation, rather than merely to bring peace to the world. He explains that Jesus, being God incarnate, came to fulfill the will of the Father and to save sinners, highlighting the importance of understanding His divine nature and mission. Reidhead also stresses that true Christmas joy comes from recognizing that Christ came to live in our hearts, transforming us and enabling us to live in accordance with God's will. The sermon calls for a personal response to invite Christ into our lives, emphasizing that He came for the lost and the broken. Ultimately, Reidhead encourages believers to fully embrace the fullness of God through Christ's presence in their lives.