Therefore, we believe and confess with our mouth as well as with our heart that all the sacraments of both the Old and the New Testaments have been ordained and instituted by God Himself, having as their purpose that all of them would point us to (as by a finger) and signify the bloody sacrifice of Christ, once performed upon the cross. It is thus beyond doubt that all the patriarchs and believers of the Old Testament have only been comforted in believing when they slew their lambs and other cattle, considering the seed of the woman (the Lord Jesus Christ) as being slain who would make full payment for the sins of the entire world. We thus view the holy sacraments as Sacrae rei Symbola ("symbols of sacred things") and invisibilis gratiae visibilia signa ("visible signs of invisible grace"); that is, they are visible signs or seals of holy things, namely, the grace of God in Christ, by which we are assured and confirmed that all of this is promised to us in His Word by God Himself and His holy prophets and apostles. We therefore believe and hold for certain that God the Lord purposed to be mindful of the foolishness of the human race, knowing how difficult it would be for the children of men to believe the naked Word of God and the pre1aching of the holy gospel. It has therefore pleased Him to place things before our eyes with which we interact daily, so that in so doing we would be all the more acquainted with this, and our faith would thereby be stirred up and strengthened and we be all the more prepared to believe the preached Word. All of this can be easily explained and understood by making a comparison with worldly things. Upon receiving a letter or document from an emperor, king, or other great lord, even though this has been signed by such a dignitary himself, we will not be satisfied with it unless a seal is attached. However, when a seal is attached to such a letter, we will be satisfied and we then may say that such an emperor, king, etc., is addressing me in what he has written.
Frederick, “The Confession of Frederick III” in, Reformed Confessions of the 16th and 17th Centuries in English Translation, ed., James T. Dennison, (Grand Rapids, Michigan: Reformation Heritage Books, 2010), 3:446-447.
Dennison’s introduction:
After the Naumburg Convention (January 20 – February 8, 1561), Frederick III, Elector of the Palatinate (so-called "the Pious;’ 1515-1576), became convinced of the Reformed faith and proceeded to transform the church in his electorate from Lutheran to Calvinist sympathies. He invited Immanuel Tremellius (1510-1580) and Zacharias Ursinus (1534-1583) to teach at the University of Heidelberg. Another Calvinist, Caspar Olevianus (1536-1587), had been teaching there since 1560. Ursinus and Olevianus would pe commissioned by Frederick to draft the Heidelberg Catechism of 1563. By 1564, following the adoption of the Heidelberg Catechism, the shift to Reformed doctrine and practice was complete.
The catalyst in moving Frederick from Roman Catholicism to Lutheranism was his first wife, Maria of Brandenburg (†1567). More particularly, what convinced Frederick to search out the Calvinist faith was the thesis on the Eucharist presented to the faculty of Heidelberg by Wilhelm Klebitz (ca. 1533-1568). Klebitz articulated and defended Calvin’s view of the Lord’s Supper, infuriating the staunch Lutheran Tilemann Hesshus/Hesshusen (1527-1588). The resolution was Frederick’s determination to study the Scriptures for himself By June 1560, a disputation between Saxon Lutherans and Heidelberg Calvinists tipped the scale towards the Reformed. Frederick then declared that the Reformed faith would be established in his realm.
The Lutherans responded on October 4, 1563, asking Frederick to summon a colloquy at Maulbronn. Reluctantly, the elector summoned a formidable gathering of Lutheran and Reformed theologians to ten sessions of debate and dispute, held April 10-15, 1564. The Lutheran doctrine of the ubiquity of Christ’s glorified body was debated in eight of the ten sessions; no agreement was reached, however. Frederick and his counterpart, Duke Christopher of Wurtemberg (1515-1568), canceled further bickering after the fruitless tenth session. The changes which Frederick had introduced into the Palatinate were preserved.
But in 1565, the Holy Roman Emperor, Maximilian II (1527-1576), demanded that the status quo ante be restored. At a session of the Diet of Augsburg (1566), Frederick declared to the Emperor that God alone had authority in this matter; he refused to abandon the revealed doctrine of the Savior, which bound his conscience. Maximilian balked and pious Frederick proceeded, less successfully, with plans to bring the Reformed faith to the (Lutheran) Upper Palatinate.
The confession below was published after Frederick’s death by his son, John Casimir (1543-1592). Some have suggested that this confession is an explanation of the Heidelberg Catechism (note the parallel in format to the Apostles’ Creed)–perhaps a "last will and testament" of the pious father. Alas, another son, Louis VI (1539-1583), would once again commit the Palatinate to Lutheranism when he succeeded his father to the throne.
The Latin text is found in Corpus et Syntagma Confessionum Fidei (1654), 141-58. Our translation is from the German text as printed in Heppe, Die Bekenntnischriften der riformirten Kirchen Deutschlands (1860), 1-18. [3:439-440]