The reverence of the seraphim is
to rebuke to the pretentious king. He had brazenly dared to usurp a role that
did not belong to him, whereas the invisible powers who received the
instruction to sing the heavenly song revealed their dread. They covered their faces
as if it were impossible for them to behold the shining brightness of the
vision that the Master offered them. They also hid their feet, signifying their
submission, demonstrating their dread, and fulfilling their role properly. As
for their flying, he is alluding to their high thoughts. Moreover, they
presented this hymn, alluding in the word Lord to the oneness of his
divine nature—because they mentioned this title in the singular—and inferring
the number of the Trinity, because they repeated the word holy three
times. The acclamation “Holy, holy, holy” indicate the Trinity, and the title “Lord
Sabaoth” signifies the oneness of his nature. In their hymn the seraphim also
praise the divine nature because it has filled not only heaven but also the
whole earth with glory. It is the incarnation of our God and Savior that
brought this to pass, because after the appearing of the Master, the nations
received the ray of the knowledge of God. (Theodoret of Cyrrhus, Commentary
on Isaiah [trans. Gerald L. Bray; Ancient Christian Texts; Downers Grove,
Ill.: IVP Academic, 2026], 24)
