A collection of twelve festival-day sermons by St. Gregory Palamas, the influential theologian and saint of the Eastern Orthodox Church. These homilies, originally composed in Greek, address the theological and spiritual significance of various feast days in the Orthodox liturgical calendar. The work represents an important contribution to Eastern Christian spiritual literature, offering insights into Palamas's theological thought and his understanding of the relationship between divine grace and human nature. This French translation makes these important religious texts accessible to French-speaking readers interested in Orthodox theology and patristic literature.