1552–1582

The Heidelberg Catechism and the rise of Reformed orthodoxy

The dispute over the Lord's Supper began in 1552 with the Hamburg pastor Joachim Westphal's book against Calvin. It produced friction within Lutheranism over Melanchthon's evasive stance. Melanchthon's followers were nicknamed "crypto-Calvinists".

Elector Palatine Frederick III wished to settle the dispute. He commissioned Zacharias Ursinus and Caspar Olevianus to write a catechism. The Heidelberg Catechism (129 questions for 52 Sundays) was adopted by synod in 1563. It expressed Reformed teaching and carried the whole Palatinate into the Calvinist camp. Lutherans, though, immediately condemned it as "Calvinist".

At the same time, thanks to Peter Martyr Vermigli and especially Theodor Beza, Calvin's successor in Geneva, predestination became the systematic core of later Reformed theology. It had not been central for Calvin himself. This theology was built on a deductive, Aristotelian method.