Deuterocanonical books
In his catechism (entitled "Explanation of the Apostles' Creed") (1533), Erasmus took a stand against Luther's teaching by asserting the unwritten Sacred Tradition as just as valid a source of revelation as the Bible, by enumerating the Deuterocanonical books in the canon of the Bible and by acknowledging seven sacraments. He identified anyone who questioned the perpetual virginity of Mary as blasphemous. However, he supported lay access to the Bible.