A more thorough explanation:

Definition: Defender of the Faith is a title given to the sovereign of England. It was first granted by Pope Leo X to Henry VIII for writing against Martin Luther. The title was later withdrawn by the Pope due to Henry's harsh regulation of the church, but it was again bestowed on the King by Parliament. The term is similar to the application of “Catholic” to the Spanish sovereign and “Most Christian” to the French sovereign.

Example: King Henry VIII was granted the title of Defender of the Faith by Pope Leo X for his defense of the Catholic Church against Martin Luther's Protestant Reformation.

Explanation: The example illustrates how the title of Defender of the Faith was first granted to King Henry VIII for his defense of the Catholic Church against the Protestant Reformation. This title was a recognition of his efforts to protect the Catholic faith and his loyalty to the Church. However, the title was later withdrawn by the Pope due to Henry's harsh regulation of the church, which led to the establishment of the Church of England. The title was then bestowed on the King by Parliament, which shows how the English monarchy had gained more power and independence from the Catholic Church.