The Defence of the Seven Sacraments (in Latin, Assertio Septem Sacramentorum) is a book, written by King Henry VIII of England in 1521. Henry started to write it in 1518, while he was reading Martin Luther's attack on indulgences. By June of that year, he had shown it to Thomas Wolsey, but it remained private until three years later, when the earlier manuscript became the first two chapters of the Assertio, the rest consisting of new material relating to Luther's De Captivitate Babylonica. It is believed that Thomas More was involved in the composition of the piece.