وَتَحْسَبُهُمْ أَيْقَاظًا وَهُمْ رُقُودٌ
You would think them awake, though they are asleep.
Aيقاظاً (awake) and ruqūd (asleep) are nominal descriptions. Both characterize the same group in opposed ways: what an observer supposes and what their actual state is.
The antithesis sharpens the striking picture: an appearance suggesting wakefulness is juxtaposed with actual sleep. This is more than listing two antonyms, because the opposing states explain the scene.
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Introduction to ʿIlm al-Badīʿ: Ṭibāq and Muqābalah
وَتَحْسَبُهُمْ أَيْقَاظًا وَهُمْ رُقُودٌ
You would think them awake, though they are asleep.
Aيقاظاً (awake) and ruqūd (asleep) are nominal descriptions. Both characterize the same group in opposed ways: what an observer supposes and what their actual state is.
The antithesis sharpens the striking picture: an appearance suggesting wakefulness is juxtaposed with actual sleep. This is more than listing two antonyms, because the opposing states explain the scene.