Letter 444: A bishop cannot content himself with having done no harm.

On the fact that the Lord received his birth according to the flesh from the seed of David. That the Lord received his birth according to the flesh from the seed of David, both Matthew and Paul and David, those divinely-inspired men, plainly declare. The one writes, "The book of the generation of Jesus Christ, the son of David" [Matthew 1:1]; the other makes it evident that our Lord has risen out of Judah according to the flesh [Paul, cf. Hebrews 7:14]; and David says, "Once I have sworn by my holiness, that I will not lie to David: his seed shall remain forever, and his throne as the sun before me; and the witness in heaven is faithful" [Psalm 88(89):36-38]. By these words he signifies the taking up of the flesh by the Lord, which is to be everlasting, as being henceforth indivisibly united to God the Word.

Ὅτι ἐκ σπέρματος Δαβὶδ τὴν κατὰ σάρκα γένεσιν ἔσχεν ὁ Κύριος, καὶ Ματθαῖος καὶ Παῦλος καὶ Δαβίδ, οἱ θεσπέσιοι, σαφῶς ἀποφαίνονται· ὁ μὲν γράφων, «Βίβλος γενέσεως Ἰησοῦ Χριστοῦ υἱοῦ Δαβίδ», ὁ δὲ πρόδηλαν, ὡς ἐξ Ἰούδα ἀνατέταλκεν ὁ Κύριος ἡμῶν τὸ κατὰ σάρκα· ὁ δὲ Δαβίδ, «Ἅπαξ ὤμοσα ἐν τῷ ἁγίῳ μου, εἰ τῷ Δαβὶδ ψεύσομαι, τὸ σπέρμα αὐτοῦ εἰς τὸν αἰῶνα μένει, καὶ ὁ θρόνος αὐτοῦ ὡς ἥλιος ἐναντίον μου· καὶ ὁ μάρτυς ἐν οὐρανῷ πιστός»· τὴν μετὰ σαρκὸς διὰ τούτων σημαίνων τοῦ Κυρίου ἀνάληψιν, ἀΐδιον ἐσομένης, ὡς ἀδιαιρέτως λοιπὸν τῷ Θεῷ Λόγῳ ἡνωμένης.