Book of Concord study · Thanksgiving
Eucharist
Psalm 100 · Isaiah 35:1–10 · Large Catechism, Sacrament of the Altar
The Texts
Psalm
"Enter his gates with thanksgiving, and his courts with praise! Give thanks to him; bless his name!" (v. 4)
Reading
"And the ransomed of the Lord shall return and come to Zion with singing; everlasting joy shall be upon their heads." (v. 10)
Book of Concord
Large Catechism, Sacrament of the Altar
Psalm 100 is the shortest complete psalm of praise in the Psalter, and its architecture is Eucharistic. It begins with a summons to make a joyful noise, moves through the gates with thanksgiving, and arrives in the courts with praise. The movement is liturgical: a procession from the outside to the inside, from the world into the presence. Luther's treatment of the Sacrament in the Large Catechism traces the same path. The believer who approaches the altar is doing exactly what Psalm 100 describes: entering the courts with the only offering a redeemed sinner has to bring.
Isaiah 35 names the travelers who make that procession. The ransomed of the Lord return to Zion on what the prophet calls the Way of Holiness, a road on which the unclean shall not pass and on which fools shall not err. They come with singing, and everlasting joy is upon their heads. Sorrow and sighing flee away. The Lutheran Confessions identify eucharistia, the Greek word for thanksgiving, as the proper name for the Sacrament precisely because what the ransomed bring to the altar is not an achievement but a song: the praise of those who received everything as a gift and know it.
Discuss
Psalm 100's movement is a procession: from outside to inside, from the world into the courts of God. How does thinking of the Lord's Supper as the destination of that procession, rather than as one element among several in a worship service, change how the congregation understands what it is doing when it gathers?
Key Terms
| Term | What It Means |
|---|---|
| Eucharistia | The Greek word for thanksgiving, which became one of the earliest names for the Lord's Supper. In it we praise and thank God for the comforting, rich, and blessed testament of Christ's body and blood. |
| Sacrifice of praise | Luther's term for the communicant's reception of the Sacrament. We do not offer Christ to God as a propitiatory sacrifice; rather, our thankful reception confesses that we are redeemed by pure grace through His death alone. |
| Food of souls / medicine | The Large Catechism's image for the Sacrament: nourishment for the new man on the journey, not a reward for those who have already arrived. Christ invites the laboring and heavy laden, not the already pure. |
| The pinch test | Luther's diagnostic for those who claim no need for the Sacrament: put your hand to your flesh and blood. If you are still in the body, you are still surrounded by sin, the world, and the devil, and you need this medicine. |
Discuss
The Large Catechism calls the Sacrament food of souls and medicine for the sick rather than a reward for the pure. Luther's pinch test asks those who feel no need: do you still have flesh and blood? If so, you still have sin, world, and devil pressing on you. Who in your congregation is most likely to stay away from the altar on the grounds that they are not ready, and what is the pastoral answer the Large Catechism gives them?
The Ultimate Thanksgiving
The Confessions make a claim that surprises many Lutherans: the Lord's Supper is the supreme act of Christian thanksgiving. The word eucharistia attached itself to the Sacrament in the early church precisely because in it the congregation praises and thanks God for the comforting, rich, and blessed testament of Christ's body and blood. When a believer receives the Sacrament to find comfort in Christ's passion, the entire ceremony becomes what Luther calls a sacrifice of praise.
The distinction Luther draws is critical. We do not offer Christ to God as a propitiatory sacrifice; that was done once and cannot be repeated. What we offer is our own thankful reception, which confesses before God and the world that we are redeemed by pure grace through His death alone. Psalm 100's command to enter His courts with praise is not a general call to a cheerful attitude. It is a specific instruction about what the redeemed bring when they approach the altar: not merit, not worthiness, not achievement, but the thanksgiving of the empty-handed.
Discuss
Luther's distinction between a propitiatory sacrifice, which earns something before God, and a sacrifice of praise, which receives and confesses what God has already given, is the hinge on which the entire Reformation understanding of the Mass turns. How does a congregation that understands the Supper as a sacrifice of praise pray, sing, and approach the rail differently from one that treats it as a religious obligation to be discharged?
Food for the Weary
The Large Catechism will not permit the Lord's Supper to be treated as a prize for the spiritually advanced. Christ's own invitation is addressed to the laboring and heavy laden, not to the already pure. Luther's warning to those who delay communion until they feel sufficiently worthy is blunt: if you wait for that moment, you will never come. The trap of waiting for worthiness is not humility; it is a refusal to accept that the Sacrament is medicine, not a reward, and that the sick are precisely the ones invited to the table.
For those who feel no distress, no hunger, and no particular need for the Sacrament, Luther offers what can only be called the pinch test. He counsels them to put their hand into their bosom to ascertain whether they also have flesh and blood. If they do, they are still surrounded by the world and the devil, still exposed to temptation, and still in need of this medicine regardless of how invulnerable they feel. Isaiah 35's Way of Holiness is not a road for those who have already arrived; it is the road on which the ransomed travel, and the Sacrament is their provision for the journey.
Discuss
The two errors Luther identifies are opposite: some stay away from the altar because they feel unworthy, and others stay away because they feel they have no particular need. Both errors share the same root assumption that their own spiritual condition is the determining factor. What does the objectivity of the gift, guaranteed by the Word rather than by the communicant's feelings, say to both groups?
The Rhythm of the Grateful Heart
The Large Catechism's most searching passage on the Sacrament is its treatment of frequency. Luther does not merely permit weekly communion; he insists that a long absence from the altar causes the heart to grow quite cold and hardened, losing all inclination and love for the Sacrament. The heart that rarely approaches is the heart that rarely needs to be ransomed, rarely feels the burden of sin and world and devil, and has effectively declared itself already in Paradise.
Luther's formulation of the problem is precise. A person who believes he can go a year or more without the Sacrament is functionally claiming that he has no sin, no flesh, no devil, no world, no death, no danger, and no hell. The Reformation removed the papal law compelling annual communion, but it replaced compulsion with something sterner: the inner urgency of the person who knows what he needs. True Christians, Luther writes, will organically urge and impel themselves toward the altar. A person who must be forced is at least moving; a person who feels no compulsion at all has a more serious problem than frequency of communion.
Discuss
Luther says the heart that stays away from the altar grows cold, and that the cold heart eventually loses the capacity to feel what it is missing. Isaiah 35 promises everlasting joy to the ransomed who come to Zion singing. What practical steps could a congregation take to move its members from treating communion as an occasional observance to experiencing it as the rhythm of the grateful heart?
The Payoff
The everlasting joy of Isaiah 35 rests on a foundation that does not shift with the communicant's spiritual temperature. Luther insists that even if a knave takes or distributes the Sacrament, the true body and blood of Christ are present, because the gift rests entirely on the sovereign Word of God and not on the moral condition of the minister or the emotional readiness of the recipient. Faith does not create what is on the table; faith receives it. Psalm 100's ransomed people enter the courts with singing not because they have become worthy of the courts but because the One whose courts they enter has made them ransomed, and the Word that did that is the same Word that guarantees what He places in their hands at the rail.