As it is written (ως γεγραπτα). The regular formula for quotation, perfect passive indicative of γραφω.

Isaiah the prophet (Εσαιου του προφητου). The same phrase in Mark 1:2 (correct text) and Matthew 3:3. Mark, as we have seen, adds a quotation from Malachi 3:1 and Luke gives verses 4 and 5 of Luke 3:40 not in Matthew or Mark (Luke 3:5; Luke 3:6). See Matthew 3:3; Mark 1:3 for discussion of Luke 4:4.