فَيَوْمَئِذٍۢ لَّا يُعَذِّبُ عَذَابَهُۥٓ أَحَدٌۭ
Sentence structure
فَيَوْمَئِذٍۢ is a time expression. لَّا يُعَذِّبُ is a negative imperfect clause; عَذَابَهُۥٓ is the object and أَحَدٌۭ the delayed subject.
Ayah summary
On that day, no one will be able to punish as Allah punishes.
فَيَوْمَئِذٍۢ — So that Day
Grammar: فَ resumes/results; يَوْمَ is an accusative time adverb and إِذٍ its genitive complement. This phrase is linked to «يُعَذِّبُ».
لَّا — not
Grammar: A non-governing negative particle before an indicative imperfect.
يُعَذِّبُ — will punish
Grammar: A Form II third-person masculine-singular indicative imperfect.
عَذَابَهُۥٓ — (as) His punishment
Grammar: عَذَابَ is the accusative object of يُعَذِّبُ; attached هُۥ is a genitive possessor.
أَحَدٌۭ — anyone
Grammar: An indefinite masculine-singular nominative delayed subject of يُعَذِّبُ.