Rhetoric and poetry can both influence an audience, but do so chiefly through different premises. Rhetoric relies on accepted or probable claims to produce persuasion; poetry relies on imagery to produce attraction or aversion.
ArtMaterialTypical result
Rhetoric (khiṭābah)Maqbūlāt, maẓnūnātProbable persuasion
Poetry (shiʿr)MukhayyalātEmotional expansion/constriction
Both may use eloquence, but their characteristic matter and aim differ.