An Orthodox Catechism is the seventeenth-century Baptist revision of the Heidelberg Catechism, prepared by the Calvinistic Baptist pastor Hercules Collins and first published in 1680. It reflects the deep theological unity between Particular Baptists and the wider Reformed tradition, while clearly expressing Baptist convictions.

Subtitled “Being the Sum of Christian Religion, Contained in the Law and the Gospel,” this work offers a warm, clear, and comprehensive summary of the Christian faith. Following the classic structure of sin, redemption, and grateful obedience, it is biblical, creedal, confessional, and deeply devotional.

Carefully edited by Michael A. G. Haykin and Stephen J. Weaver Jr., this edition makes a historic Baptist treasure accessible for today’s church. It is a faithful guide for believers of every age, strengthening them in the faith once delivered to the saints and equipping them to serve Christ with clarity, conviction, and joy.