With the service often running late, it's not surprising that the service surrounding the celebration of the Lord's Supper is often truncated. While none of the specific elements contained in the communion liturgy are expressly commanded in Scripture, this part of the service contains some of the oldest parts of the liturgy, specifically, the Preface. Far from simply preserving something from the past, however, these texts serve to give voice to our thanksgiving for the gifts that we are about to receive.