Crypto-Calvinists

Crypto-Calvinism is a term for Calvinist influence in the Lutheran Church during the decades just after the death of Martin Luther (1546). It denotes what was seen as a hidden (crypto- from Greek: κρύπτω meaning "to hide, conceal, to be hid") Calvinist belief, i.e., the doctrines of John Calvin, by members of the Lutheran Church. The term applied to those Germans, who secretly held or were accused of holding the Calvinist doctrine of the Eucharist.

The term crypto-Calvinist in Lutheranism was preceded by terms Zwinglian and Sacramentarian. Also, Jansenism has been accused of crypto-Calvinism by Roman Catholics.

Martin Luther had controversies with "Sacramentarians", and he published against them, for example, in his The Sacrament of the Body and Blood of Christ—Against the Fanatics and Confession Concerning Christ's Supper. Philipp I of Hessen arranged the Marburg Colloquy in 1529, but no agreement could be reached concerning the doctrine of Real Presence. Subsequently, the Wittenberg Concord of 1536 was signed, but this attempt at resolving the issue ultimately failed.

While Lutheranism had weakened after the Schmalkaldic War and Interim controversies, the Calvinist Reformation was spreading across Europe. Calvinists wanted to help Lutherans to give up "remnants of popery", as they saw it. By this time Calvinism had expanded its influence to southern Germany (not least because of the work of Martin Bucer), but the Peace of Augsburg (1555) had given religious freedom in Germany only to Lutherans, and it was not officially extended to Calvinists until the Treaty of Westphalia in 1648. While Bullinger, Zwingli's successor, in 1549 had accepted Calvin's much less radical view of Christ's presence in the Lord's Supper (the Eucharist was to be more than a sign; Christ was truly present in it, and was received by faith), Calvinist theologians thought that Lutheran theology also had changed its view to Real Presence, because the issue was not discussed anymore, and Philippist teaching gave some justification to this conclusion.

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