The offering is the pinnacle act in worship. Likewise, all of worship is an offering. The self-emptying of Jesus is the model. Unless a person offers the total self to God, true worship does not occur.

Actions devoid of self-giving do not qualify as the worship of God regardless of the ecclesiastical nature of the site where they happen, the spiritual flair with which they are performed, or the holiness of the language which accompanies them.

…So central in the Christian life is the concept of offering that during the first three centuries after Jesus’ ministry, a Christian was called an “offerer.” The terminology by which Christians are known has changed. But the centrality of offerings in Christian experience remains.

The offertory time in public worship deserves careful attention. What happens in this period is indicative of the nature of the whole worship experience.

from The Gift of Worship