The Sacrament of the Body and Blood of Christ—Against the Fanatics is a book by Martin Luther, published in late September or early October 1526 to aid Germans confused by the spread of new ideas from the Sacramentarians.

The real presence of Christ's true body and blood in the Lord's Supper was a controversial issue at the time of Luther.

The Sacramentarians Andreas Karlstadt,[2] Valentin Krautwald, Caspar Schwenckfeld,[3] Huldrych Zwingli, and Johannes Oecolampadius were open combatants against Luther on this topic.

[5] Since this work included forewords from both Luther and Philipp Melanchthon, it gave the appearance that the Wittenberg faculty agreed with Zwingli.

[4] Inspired by Bucer's tactics,[7] Leo Jud put forth an essay in Zürich claiming that Luther agreed with the Swiss understanding of the Lord's Supper.

[2][8] After editing them and apparently adding extra material[9] without Luther's involvement,[8] the printer published them sometime in late September or early October 1526 under the name The Sacrament of the Body and Blood of Christ–Against the Fanatics.

The Sacrament of the Body and Blood of Christ opens with a two part exposition of the Christian faith as applied to the Lord's Supper.

Luther prevents pantheism from joining the discussion table by limiting the search for Christ to what God's Word alone has authorized.

In it, Luther rejects the papal use of the sacraments as good works that humans could perform to merit salvation[23] or as a means of raising money.

[24] Although he rejects the symbolical interpretation of the Lord's Supper,[25] he advocates that the sacrament be conducted along with general preaching and proclamation in the lives of ordinary Christians.

By rejecting the Pope's commands regarding the sacrament, they bore witness to the Gospel, showing that the believer, in Christ, was "free from death, devil, and hell…a son of God, a lord of heaven and earth".

In contrast to this faith in Christ, which is formed at once from the word, the second principle of Christian doctrine can be learned for an entire lifetime without completely mastering it.

Indeed, this application is so rich in meaning that, along with faith, love, and patience, it provides so much for a Christian to strive for that there is no need to indulge in obscure studies to prove academic greatness.

[31] Private confession is not to be eliminated, because it retained its value through the giving of individual comfort to troubled souls and the providing of an opportunity for spiritual growth.

[38] Luther's custom of referring to those who opposed him in non-Christian terms in The Sacrament of the Body and Blood of Christ sounds unusual to modern ears and therefore merits discussion.

[39] In Zwingli's view, Luther was only a Christian as any other and his talents as a theologian did not give him the right to make tyrannical judgments,[40] for example, terming him a heretic, fanatic, and sacramentarian.