The essence of our study consists in the selection of scriptural verses from the works of St. Irenaeus of Lyons on the Virgin Mary: Acts 3, 15-16; Acts 49, 11; Isaiah 7, 14; Daniel 2, 34-35; Micah 5, 1-2; Matthew 1, 20; Luke 1, 26-38, Galatians 4, 4. From the interpretation given by Saint Irenaeus to these verses, we will identify and present the elements of liturgical spirituality that form the theme of the Annunciation feast: the parallel between the old Adam and the new Adam, the parallel between Eve and the Virgin Mary, Eveʹs disobedience – Virgin Maryʹs obedience, Eveʹs disbelief – Virgin Maryʹs faith, the renewal of Eve in the Virgin Mary, the old man – the new man, the old creation – the new creation. Being faithful to the Holy Scriptures and his predecessors, Saint Irenaeus of Lyons contributes to the development of Mariological theology through his exhaustive arguments on the parallel between the Old Adam and the New Adam, including the parallel between Eve and the Virgin Mary, a parallel which has Christological, Mariological, anthropological, cosmological and soteriological implications.