Repetition is normal and natural within the system of oral composition-in-performance in which the Iliad was composed, and these lines repeat Hektor’s charge for the spying mission at 10.309–312. Each of the lines 10.397–399 is marked with an obelos in the Venetus A: see on 10.51–52 for the Alexandrian scholarly practice of athetesis. The scholia, however, tell us that there is some dispute about whether Aristarchus indeed meant for the obeloi to be placed here: one scholion says that they should be, if we can trust the work of the scholar Ammonios. The second scholion informs us both that, in the work of the scholar Nemesion, he states that no reason for the obeloi is found in the hupomnēmata of Aristarchus, and that the work of Ammonios says that Aristarchus did place those signs in the margin, but in the end took them out. All of this serves as a reminder that we have access to Aristarchus’ work only as mediated by his successors.
The scholia also inform us that there are recorded differences in how this particular repetition operates: in the version in the main text of the Venetus A, Dolon has changed the person of the verb from Hektor’s third person—find out whether they are making plans—to the second person—find out whether you are making plans—now that Dolon is speaking to those on whom he was intending to spy. (This change seems to be the reason why 10.398 also has the critical mark of a diplē next to it in the Venetus A, which indicates a comment about the language used.) We can compare 10.409–411, where Odysseus repeats the questions that Nestor had given as the charge for their mission. He retains the third-person plural verbs that refer to the Trojans (those lines are marked with obeloi and also with asterisks in the Venetus A, indicating that they are repetitions). The A main scholia indicate that it should still be the third person here, while the intermarginal scholia note that in other manuscripts these verbs are indeed in the third person. If we compare this type of repetition to messengers delivering their message, however, we do find that a pronoun change often happens. For example, when Zeus sends Dream to Agamemnon, he orders him using imperatives and the third-person pronoun for Agamemnon (e.g. “Tell him to arm the Achaeans, who have beautiful hair,” Iliad 2.11), but when Dream speaks to Agamemnon, he uses indicative verbs and the second person (“He has told you to arm the Achaeans, who have beautiful hair,”
Iliad 2.28), keeping all other words the same. Similar changes naturally happen, as we can see also at Iliad 9.157, where Agamemnon is speaking about Achilles in the third person, and Iliad 9.299, where Odysseus is delivering the message to Achilles himself. The formulas have such flexibility.
This phenomenon seen within repeated passages and the disagreement over whether it is the second or third person in 10.398 suggests that this passage is in fact playing on the conventional repetition by messengers. Dolon, after all, was supposed to gather information about the Achaeans and report it back to Hektor. He is not a messenger, and therefore he was not supposed to repeat Hektor’s words to anyone else. When Odysseus likewise repeats Nestor’s questions (10.409–411), he is in the process of obtaining the answers he seeks, not confessing what he was sent to find out, as Dolon is. We noted above (10.314–315) that there is an implicit contrast between Dolon the spy and his father the herald, and here, when Dolon repeats what Hektor asked him to find out, he seems to be doing so more in the mode of the herald he was not supposed to be.