In this installment of his "Creeds and Confessions" series, Don Arndt transitions from the early church creeds to the larger, more detailed documents known as confessions of faith. After briefly reviewing how creeds like the Apostles', Nicene, and Athanasian Creeds addressed specific doctrinal challenges, he explains that confessions serve as comprehensive systematic theologies—clarifying truth, guarding against error, promoting unity, and functioning as teaching tools. The bulk of the lesson focuses on the Westminster Confession of Faith (1646), which Arndt identifies as arguably the most influential confession in Protestant history. He traces its origins in the English Civil War, its production by 150 theologians at Westminster Abbey with over 4,000 biblical references, its unexpected adoption by the Church of Scotland rather than the Church of England, and its lasting impact on Presbyterianism and Reformed Baptist theology—particularly through the 1689 Second London Baptist Confession, which retained Westminster's Calvinist soteriology while correcting its positions on baptism and church government. Arndt also addresses the strengths and dangers of confessions, including the risk of elevating them above Scripture and questions of subscription requirements, before discussing practical questions of inter-denominational cooperation, the importance of drawing doctrinal lines, and the consequences visible in mainline Protestant churches that have abandoned their confessional commitments.