The fifth and last volume of Irenaeus’s trilogy, “Irenaeus Against Heresies V5,” continues the author’s thorough refutation of Gnostic teachings. This book disproves the fairly fanciful readings of the Gnostics by concentrating on the significance of Paul’s epistles and the teachings of Jesus. It offers proof of a true resurrection, including venerable Church customs inherited from the apostles. The book is a useful tool for comprehending the nuances of the fight against Gnosticism.