«يَكَادُ زَيْتُهَا يُضِيءُ وَلَوْ لَمْ تَمْسَسْهُ نَارٌ»
“Its oil almost shines even though fire has not touched it.”
The verb yakādu presents a degree as nearly reached rather than simply asserting that it has occurred. Such approximation can make very strong expression intelligible and rhetorically effective.
The source also discusses takhyīl, the creation of an imagined scene, as a way extreme description may become acceptable. In such cases the reader understands a poetic image rather than a literal report. Wit and playful exaggeration can serve similar context-dependent functions.