«أَرْعَى الْجَارَ وَلَوْ جَارَ»
I respect the neighbour even if he acts unjustly.
The first al-jār is the noun “neighbour”; the second jāra is a past-tense verb meaning “acted unjustly.” Their similar sound and different functions create paronomasia (jinās).
Arʿā is a first-person imperfect verb: “I care for / regard.” The speaker claims not to abandon courtesy because of another's bad conduct. This should not be read as approval of injustice or a demand to give up reasonable self-protection.