"The Errors of Catholicism" is a concise yet penetrating examination of several core Catholic doctrines, measured carefully against the plain teaching of Scripture. Dr Robert Moreton addresses subjects such as Mary's alleged immaculate nature, demonstrating from the Bible that she was a sinner in need of a Saviour and that she had other children after the birth of Christ. He dismantles the notion of Purgatory by showing that salvation is complete at the moment of faith, not through post‑mortem purification, and he contrasts Catholic teaching on works‑based salvation with the biblical declaration that justification is by grace through faith alone. The book also exposes the unbiblical practices of praying to and venerating Mary, and the saints, and it critiques sacramental confession by highlighting the New Testament's insistence that believers pray directly to God. Through clear exposition and careful use of Scripture, Dr Robert Moreton sets forth the biblical position in contrast to the traditions upheld by Catholicism.