The central message of the sermon is that worship is not limited to a specific activity or ritual, but rather it is an ongoing process of attributing ultimate worth to something. Worship involves recognizing that there is nothing more valuable or desirable than the object of one's worship, which can be God or anything else that holds supreme value. The teacher highlights that this concept of worship is present in everyday life, as people constantly weigh the costs and benefits of various things and decisions, asking themselves if they are worth it. Ultimately, the sermon encourages listeners to reflect on what or whom they worship, recognizing that our lives are an ongoing cost-benefit analysis, and that we must consider whether what we value and pursue is truly worth it in relation to God's ultimate worth.