Possible Clues:

• Follower of "Agnus" or "Opus"
• Montemezzi's 'L'Amore ___ Tre Re'
• "Agnus ___" (mass hymn)
• Opus __
• Workplace initialism whose middle letter stands for "equity"
• ___ Fratelli (tomato sauce brand)
• Agnus — (lamb figure)
• "— gratia" ("by the grace of God")
• Agnus — (Mass prayer)
• Gods, in Italy