These lines are the same as those at Iliad 17.76–78. There, Apollo, in disguise as Mentes, leader of the Kikones, warns Hektor not to chase after Achilles’ horses, which carried Patroklos into battle (see also Iliad 16.864–867, where we are reminded that the gods gave these horses as a gift to Peleus). For this traditional language expressing a prohibition against Achilles’ enemies capturing these horses, see above on 10.330.