In this sermon, we are introduced to the foundational truths about what it means to be a Christian. Through Paul's greeting in Ephesians 1:1-2, we learn the significance of being a "saint," "faithful," "united," and recipients of "grace" and "peace." The sermon emphasizes the depths of God's grace and the new identity believers receive through their union with Christ. The sermon also highlights the importance of understanding Christian doctrine and living it out in everyday life.