"Come, O worshippers of the heavenly Trinity, and let us praise the earthly trinity of divine Hierarchs..."

The Holy Three Hierarchs Sts. Basil the Great, Gregory the Theologian and John Chrysostom (source)

  
Come, O worshippers of the heavenly Trinity, and let us praise the earthly trinity of divine Hierarchs: Gregory, the namesake of theology, Basil, who bears the name of the Kingdom, and John, whose name is truly filled with grace. They sail the deep of wisdom, and the streams of the ocean of the Spirit, and ever draw forth living water from the spring welling forth to [eternal] life, they shine forth like pearls, the rudder of the Church, the tree greatly-laden with fruit, the stewards of grace, the mouth of Christ, the defenders of the Trinity, from whom we immediately are enlightened, and who ceaselessly entreat on behalf of our souls.
-Idiomelon of the Litia for the Feast of the Three Hierarchs
  
(source)
  

Through the prayers of our Holy Fathers, Lord Jesus Christ our God, have mercy on us and save us! Amen!