Pseudo-Chrysostom — as excerpted in the Catena Aurea on Mark 1:2-3

“(Vict. Ant. c. Cat. in Marc.) But it may be said that it is a mistake of the writer. Otherwise it may be said, that he has compressed into one, two prophecies delivered in different places by two prophets; for in the prophet Isaiah it is written after the story of Hezekiah, The voice of one crying in the wilderness; but in Malachi, Behold, I send mine angel. The Evangelist therefore, taking parts of two prophecies, has put them down as spoken by Isaiah, and refers them here to one passage, without mentioning, however, by whom it is said, Behold, I send mine angel.”