The work of Saint Irenaeus "Detection and Overthrow of the False Knowledge" is of great importance in order to understand the Gnostic systems and theology of the early Church. The accurate presentation of the Gnostic systems, which we find in his work, is today a reliable source of the history of heresies. Saint Irenaeus undertook the tremendous struggle to combat heresy and ensure the safety of the faithful. He is rightly considered the founder of the Church's anti-heretical struggle. His struggle and contribution earned him great fame and the title of saint in the Church, and his influence on the Church was universal and decisive for its victorious and glorious course. The respect and authority of Irenaeus' personality is evident from his general ecclesiastical recognition, to the point that even Victor of Rome set aside early tendencies of papal primacy in the face of the peaceful intentions and interventions of Irenaeus, "the one surnamed Peace". Therefore, it was rightly said that "Saint Irenaeus was to his time what Athanasius the Great was to his own time" (Brunner).