Presbyterian churches explicitly exclude the Shepherd of Hermas from the biblical canon. This early Christian text, composed in the second century CE (likely between 100-140 CE), is a visionary and allegorical work treating repentance and Christian moral living. While it was occasionally cited as authoritative in some early church contexts and appears in some ancient biblical manuscripts, it was ultimately not accepted as canonical Scripture. The Westminster Confession of Faith (Chapter I) establishes that the canon of Scripture consists of the 66 books of the Old and New Testaments, with no additional writings recognized as authoritative.

The Shepherd of Hermas is excluded because it is a post-apostolic writing — composed after the death of the apostles and therefore outside the apostolic era. The principle of apostolicity is central to Presbyterian understanding of biblical canon: only writings from the apostles themselves or those standing in direct apostolic authority are recognized as Scripture. The Shepherd of Hermas may have historical interest as evidence of early church teaching on repentance, and it is sometimes read in academic or devotional contexts, but it possesses no binding authority in Presbyterian churches. This reflects the Reformed commitment to sola scriptura — Scripture alone as the rule of faith and practice — and the conviction that the apostolic canon was closed with the New Testament writings.