The sermon focuses on the theme of hospitality, drawing from 2 John and the broader biblical context. It emphasizes that hospitality is not just a cultural practice but a Christian virtue rooted in love and service to others. The speaker highlights how hospitality can be a powerful witness for Christ, encouraging believers to open their hearts and homes to others. The sermon also touches on the importance of face-to-face relationships and how the church can embody hospitality as a reflection of God's love.