Antiphona ad Magnificat

This antiphon presents a direct petition to the guardian angels: 'Sancti Angeli, Custodes nostri, defendite nos in proelio' (Holy Angels, our guardians, defend us in battle). The 'proelium' (battle) is the spiritual combat against the devil and his angels - the same warfare St. Michael wages in heaven is continued by guardian angels on earth. The motivation clause 'ut non pereamus in tremendo judicio' (that we perish not in the dreadful judgment) connects angelic protection to eschatological salvation. At First Vespers, this antiphon establishes the feast's spiritual warfare motif: guardian angels are not merely comforters but warriors assigned to each soul's defense.