Why did Prince Henry wear a prickly shirt made of hair next his skin?

Prince Henry, known as Henry the Navigator, wore a prickly shirt made of hair as a form of self-discipline and penance. This uncomfortable garment served as a reminder of his commitment to a life of virtue and humility, reflecting his dedication to exploration and the support of maritime endeavors. It symbolized his ascetic lifestyle and the sacrifices he made in pursuit of knowledge and discovery.