وَكَذَّبَ بِٱلْحُسْنَىٰ
Sentence structure
وَكَذَّبَ is a coordinated Form II perfect with understood subject. بِٱلْحُسْنَىٰ is a prepositional phrase linked to it.
Ayah summary
He rejects the best truth as false.
وَكَذَّبَ — And denied
Grammar: وَ coordinates; كَذَّبَ is a Form II perfect with understood subject هُوَ.
بِٱلْحُسْنَىٰ — the best
Grammar: بِ is a preposition; the defined feminine noun is genitive in position. This phrase is linked to «كَذَّبَ».