Institutes of the Christian Religion

Institutes of the Christian Religion (Latin: Institutio Christianae Religionis) is John Calvin's seminal work of Protestant systematic theology. Highly influential in the Western world and still widely read by theological students today, it was published in Latin in 1536 (at the same time as the Henry VIII of England's Dissolution of the Monasteries) and in his native French language in 1541 (it was a landmark in the elaboration of the French language in the 16th century to become a national language) with the definitive editions appearing in 1559 (Latin) and in 1560 (French).

The book was written as an introductory textbook on the Protestant faith for those with some previous knowledge of theology and covered a broad range of theological topics from the doctrines of church and sacraments to justification by faith alone and Christian liberty. It vigorously attacked the teachings of those Calvin considered unorthodox, particularly Roman Catholicism to which Calvin says he had been "strongly devoted" before his conversion to Protestantism.

The Institutes is a highly regarded secondary reference for the system of doctrine adopted by the Reformed churches, usually called Calvinism.

John Calvin was a student of law and then classics at the University of Paris. Around 1533 he became involved in religious controversies and converted to Protestantism, a new Christian reform movement which was persecuted by the Catholic Church in France, forcing him to go into hiding. He moved to Basel, Switzerland, for safety in 1535, and around this time he must have begun writing a summary of theology which would become the Institutes. His Catholic opponents sought to associate him and his associates (known as Huguenots in France) with radical Anabaptists, some of whom had been defeated after a long siege in the Münster Rebellion in June 1535. He decided to adapt the work he had been writing to the purpose of defending Protestants suffering from persecution from false accusations that they were espousing radical and heretical doctrines. The work, written in Latin, was published in Basel in March 1536 with a preface addressed to King Francis I of France, entreating him to give the Protestants a hearing rather than continue to persecute them. It is six chapters long, covering the basics of Christian faith using the familiar catechetical structure of the Ten Commandments, the Apostles' Creed, the Lord's Prayer, and the sacraments, as well as a chapter on Christian liberty and political theology. Soon after publishing it, Calvin began his ministry in Geneva, Switzerland.

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