Fidei Defensor, "Defender of the Faith"

de bene esse: literally, of well-being, morally acceptable but subject to future validation or exception

The title of Fidei Defensor, "Defender of the Faith", was conferred by Pope Leo X on Henry VIII on 11th October 1521. This was a reward for Henry VIII writing his pamphlet Assertio septem sacramentorum adversus Martinum Lutherum ("Declaration of the Seven Sacraments Against Martin Luther"), defending the Catholic Church against the works of Martin Luther. 

You can read Henry VIII’s Assertio Septem at http://archive.org/details/assertioseptem00henruoft