This is a study of the church's formulation of its teaching ministry in periods preceding our own, particularly in the Reformation era. The author finds that the office of doctor or teacher, like the offices of pastor, elder, and deacon, was postulated by Calvin as an integral part of the public ministry. In a preliminary historical review Dr. Henderson surveys the conditions obtaining in northern Europe during the Renaissance as a background to understanding the situation that Calvin found in Geneva. He then studies the doctoral office as it existed in sixteenth-century Switzerland, France, the Netherlands, and Scotland, through which Continental Calvinism was transmitted to the British Isles. In turning to the English Puritan understanding of the doctoral office, Dr. Henderson examines the Tudor university ''reform, Martin Bucer's ideas regarding the reformation of all English education, the experiences of the Marian exiles in the practice of the Reformed church life, and the attempts under Elizabeth and James I to presbyterize the Church of England. The study reaches its climax with the account of the debates of the Westminster Assembly between the thirteenth and the twenty-first of November, 1643, wherein it developed that there were three British groups holding different views of the doctoral office: the Presbyterian Puritans, the Church of Scotland commissioners, and the Independents. Finally, Dr. Henderson deals with the understanding of the doctoral ministry after the time of Westminster, particularly with the developments that occurred in the Church of Scotland, in American Presbyterianism, and in American Congregationalism. He believes that a continuing discussion of this office is a prerequisite to understanding the church's ministry as a whole. The book represents the only piece of original research ever done on the subject.