"Dies Irae, Dies Illa" - is a famous medieval church hymn that has become an integral part of the requiem mass. Its title translates to "Day of Wrath, that day," and it serves as a powerful reminder of Judgment Day, when, according to Christian teaching, the final judgment of souls will take place. The hymn is based on a biblical prophecy from the Book of Zephaniah, which describes the dreadful day when the Lord will come to judge the world. The texts of the hymn convey themes of fear, repentance, and hope for mercy. It depicts apocalyptic imagery, such as the destructive forces of nature and the appearance of angels calling to account for deeds done on earth. The structure of the hymn consists of several stanzas, each enhancing the atmosphere of anxiety and anticipation. They raise important questions about life, death, and eternity, creating a profound emotional connection with believers. "Dies Irae" is often performed in the context of funeral rites, emphasizing grief and remembrance of the departed. Over time, the hymn has inspired many composers, including Mozart and Verdi, who have incorporated it into their musical works. "Dies Irae" continues to be an important element of Christian tradition, provoking reflections on the meaning of life and the inevitability of each person's fate.