General Francois de La Noue likely means that the brutal and divisive wars fought over religious differences in France (such as the French Wars of Religion in the 16th century) caused people to lose sight of the true principles and teachings of their faith. Instead of practicing and embodying their religious values, individuals became consumed by violence, hatred, and intolerance towards those who believed differently. The focus on winning and asserting dominance in religious conflicts overshadowed the spiritual aspects of their religion, leading to a disconnect between religious beliefs and actions.
