Servius
Servius's commentary on Virgil's Aeneid, thought to be based on an earlier commentary by Aelius Donatus (4th century CE), provides a good insight into common understandings concerning Laocoön at the turn of the 5th century CE. In his notes on Aeneid 2.201–31, Servius cites Euphorion as his principle source. His note is also our source for Bacchylides' account of Laocoön, and mentions that the names of the sea dragons that attack Laocoön and his sons are given in Sophocles' account.
Like Euphorion (and Sophocles), Servius writes that Laocoön's sin was having sex with his wife (Antiopa) before the statue of Apollo in his temple. This, says Servius, was the generally understood history of Laocoön, thereby indicating that readers would have known that background of the man selected, in Virgil's account, by the Trojans to be Neptune's priest. In not knowing the real reason for the attack on the priest, writes Servius, the Trojans are given some excuse for having thought Laocoön was punished for throwing his spear at the Greek’s horse.
Servius's subsequent mention of the Trojan king Laomedon as having treated Neptune with contempt introduces a further context for Laocoön's death that Virgil's readers would have known. In book 11 of Ovid's Metamorphosis, Apollo and Neptune put on mortal form to build Troy's walls (see image above). Laomedon then refuses to pay them and claims that they are lying about undertaking the work, for which affront Neptune swears vengeance.
Laocoön's punishment is therefore linked in Servius's commentary to both individual and collective sins: Laocoön's desecration of Apollo's temple; Laomedon's contemptuous treatment of Apollo and Neptune; and Troy's selection of a sacreligious man as the successor of a priest of Neptune (also named Laocoön).
On the retreat of the sea-serpents to Minerva's temple, Servius observes that either she was also an enemy of Troy, or this is a sign of the destruction of the city.
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