Noting how the repetition of κλίνω in these lines at the opening of Iliad book 22 contrasts the Trojans leaning on their battlements with the Achaeans leaning their shields on their shoulders. Book 22.2-4.
κεκλιμένοι καλῇσιν ἐπάλξεσιν: αὐτὰρ Ἀχαιοὶ
τείχεος ἆσσον ἴσαν σάκε᾽ ὤμοισι κλίναντες
“they leaned on their beautiful battlements; but the Achaeans / drew near the wall, their shields leaning on their shoulders.”
So shields are contrasted with battlements, as a means of self-defense, yes; but also, the Trojan battlements are leaned on, indicating exhaustion, or a need for shelter, while the Achaean are leaning their shields on their shoulders, indicating, I’m not sure what: maybe that they don’t anticipate using them?
Finally, there is a curious symmetry to the syntax of these lines: with “leaning” serving as bookends, “walls” (teixos — another defensive work) occupying a middle ground between them; and “battlements” and “shields” occupying a middle point between them.
.i`` * ^ / . . . . . ` `~ 